Well, I'm glad I didn't keep looking through all those Turner families for Moses as a child still at home, you already knew who his parents were.
"Republic of Texas: Poll Lists for 1846", compiled by Marion Day Mullens shows:
Turner, S.S., Red River Co. Turner, Samuel, Brazoria Co. Turner, Samuel, Guadalupe Co. Turner, Samuel, Jasper Co.
Is your Samuel listed in one of these counties on the 1850 census?The census index online I have access to does not have an index for the 1850 census, yet.
You might check out land records for these men.Although records usually show they are residing in the county where they are buying, occasionally you will luck out and they will say where they are from on that first purchase, that might get him "out" of TX.LOL