Howdy,
After several searches I have been unable to locate a "specific Buffalo Station." However, I think you may need to repost your message on the Indian Territory board.
Doing a search on "Buffalo Station" on the Indian Territory board I found one posting by Patricia Adkins Rochette on 7 Dec 2004 titled: Shilo Trading Post where I found "carries to Buffalo Station (Clay Co, Tx)." However, I could not find any reference to Buffalo Station on a Clay Co, Tx, web site.

I also found a little information regarding the Second Battle of Cabin Creek at http://members.aol.com/swarren385/cabincreek/ which claims that the 30th TX Cav was involved in that fight in Mayes Co, OK (northeastern part of the state) on 19 Sep 1864 (a long ways from Clay Co, TX). Logic (?) would suggest that your ancestor might have been closer to that area as the 30th TX Cav was also listed as a participant at the battle at Poison Spring (Ouachita Co, AR) 18 Apr 1864. A brief outline history of the 30th can be found at www.itd.nps.gov/cwss/ under regiments.

Hope this helps a little,
Bobby