Its a Texas plate EXTREMLY common with Texas reenactors, (been plenty guilty myself). That being said that style of buckle did exist, but it looking to be lead filled makes me suspicious, I'm not an expert on buckles, (there's plenty here though), but my immediate suspicion is its a fake. Most surviving photos of Texas troops bound for Virginia, (and glory), doesn't show that particular pattern of buckle, most I've seen anyway, and often depict simple black iron "roller" buckles, and sometimes other styles of brass Texas buckles, with square ones being prominent.
There were many, many styles of Texas brass buckles, some patterns dating back to the Republic period, from 1836-1845, and the vast majority, if not all I've seen from the Virginia theater were several of the square variants, (one I've seen was actually a Republic of Texas Army buckle lol), and while I won't say for sure, my personal suspicion is you have an older reenactor buckle.
Either way welcome to CivilWarTalk.