Due to the short six-month term of state service, there's very little in this man's record that would help you. It does demonstrate that Sam Gray was alive during 1863-64 while in state service, so he must have died at some later date.

As seen in the subject title, members of this regiment enlisted to serve the State of Texas rather than the Confederate government. At the risk of being annoying, please note that the branch of service should be spelled Cavalry, not Calvary. The later is the name given to the place where Christ was crucified.