The discussion below re Company H, "Claiborn Invincibles" derives from a rather long thread on this message board which should provide you with greater detail of the 17th Louisiana's history.

In the Cedar Hill Cemetery, Soldiers Rest, Vicksburg City Cemetery, there is an entry for one:

Lieut. ______ Lace, 17th Louisiana, died June 14, 1863, buried in Potters Field Grave No. 37, UDC Record Page 37, w/notation, "Still had a headstone in 1905]

Note, there was no Lt. Lace in the regiment. I believe the man so buried is your Lt. Leake even though the date of death may be in error.

His original grave marker has long ago rotted and we no longer are able to identify original graves.

If the older grave stone still exists, I believe it would be in an area with other old stones in the upper right hand corner of Soldiers Rest.

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M. C. Leak, Private/1st Lieutenant, (2nd) Company H, 17th Louisiana Infantry, enlisted May 23, 1862[?], last recorded present on the Jan & Feb, 1862 muster roll, wounded at Vicksburg May 30, 1863, died of his wounds June 5

Note: His service record file is much too faint to read on-line. These records may be obtained through the service noted in the Red enclosed box above.

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17th Regiment, Louisiana Infantry

17th Infantry Regiment was organized at Camp Moore, Louisiana, in September, 1861. Its members were recruited in the parishes of Ouachita, Sabine, Catahoula, Plaquemines, Orleans, Caddo, Bossier, Morehouse, and Claiborne. The unit fought at Shiloh and in July, 1862, contained 27 officers and 373 men. Assigned to Baldwin's Brigade in the Department of Mississippi and East Louisiana, it lost 2 killed, 10 wounded, and 1 missing at Chickasaw Bayou, then was captured at Vicksburg on July 4, 1863. Exchanged and reorganized, the regiment was placed in A. Thomas' Brigade, Trans-Mississippi Department, and engaged the Federals within the boundries of Louisiana. Early in 1865 it disbanded. The field officers were Colonels S.S. Heard and Robert Richardson; Lieutenant Colonels Charles Jones and Madison Rogers; and Majors Robert B. Jones, William A. Maddox, William A. Redditt, and David W. Self
http://www.itd.nps.gov/cwss/regiments.cfm

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Company H, "Claiborn Invincibles"

" ....The company was re-organized on May 21st, 1862, at Edwards, Mississippi, electing as officers, G. M. Kilgore, Captain; M. C. Leake, 1st Lieutenant; A. L. Harper, 2d Lieutenant; and J. D. Hamilton, 3d Lieutenant. We were in action at Chickasaw Bluff, having been detached as skirmishers to meet the enemy. The company did good service here, led by Capt. Paul Hamilton of Gen. S. D. Lee's staff, a gallant South Carolinian who lost his life in this action. The Orderly Sergeant of the company, S. J. McDonald, lost a leg here, which was the only casualty suffered by the company.

"The company was next actively engaged at the battle of Port Gibson, on the first of May, from 12 o'clock till 6 o'clock in the evening, in which Privates C. T. Murphey and W. H. Baker were killed. On the 2d of May we retired to Vicksburg, and hence were again ordered to Baker's Creek, but were not called into action there, the engagement being virtually over when we arrived. From that point we again went into the trenches around Vicksburg, which was closely invested by the Union army until the surrender of the entire garrison. During this period the company saw hard times and suffered some of the worst experiences of a soldier's life, harassed by shot and shell by night and day, constantly on the alert to repulse assaults, and never sure of an hour's rest. In addition to these discomforts, we were on short rations in the last days of the siege, the daily allowance running as low as seven ounces of bread and four of pork, and finally the ration of bread was reduced to four ounces per day for each man. It was at this time that mule steaks came into favor. Here the company suffered a loss in death of First Lieutenant Leake, who was wounded on May 30th, and died on June 5th, 1863. A. L. Harper was now promoted to be First Lieutenant, J. D. Hamilton to be Second Lieutenant, and J. H. Hay was elected by the company Third Lieutenant. On the 19th of May, in the first assault of the enemy on our works, Private H. B. Dansby was killed and Young Shorty (sic.) severely wounded. On the 16th of June, Private W. R. Arthur was killed, and S. B. DuBose seriously wounded by the explosion of a shell. On the 22nd of June, Probate (sic.) J. W. Thornton did of wound received on the 20th. The above constitute the losses of the company in action, so far as remembered. Our good fortune in not losing more men can only be attributed to the fact that the company was almost constantly held in reserve for emergencies that never came. . . . ."
http://history-sites.com/cgi-bin/bbs53x/lacwmb/webbbs_config.pl?noframes;read=12565