ORIGINAL: txhunter58
You should really take a look at the new Knight KRB7 rolling block. Initial reports are outstanding. Here is a link that has them for $278, still within your buget if you add $3. I don't think you will find a better gun out there at that price. May be able to find them cheaper elsewhere. This was just the first link I found.
http://www.tjgeneralstore.com/knight.htm
That would be an excellent deal for a new rolling block. Bryce Towley (sp) had a write up on this rifle in American Riflemen 2 issues ago, it was a good write up. Can't go wrong with a Knight. Chap Gleason