Here's my .02 of suggestions:
1. 45-70 barrel, since I don't see a big bore mentioned in your post.
2. 223 barrel, just because it's cheaper to shoot, and a good time.
3. If you really have the bug for something different, take the 700 bucks, and pick up a Contender carbine in 30-30 or 7-30 Waters. That should work for your N. Texas hunting needs inside 200 yards, maybe a bit more.
Whatever you get, I wish you well, and hope you get plenty of field time with it.
Regards
Mike