I think Kelsey has given some good advice.  Getting a decent bari in good working condition, and suited for you individually, for $2500 would be tricky.  You might find a used American bari from the 1960s for that price, but then you'd probably get hit with a substantial bill for an overhaul as well.  Baris are expensive to maintain as well as to purchase.  Then there's a good chance that one of those older horns might not be suited for you.  Not a venture for the faint of heart.  Think long and hard about yourself as a bari player, your commitment level, what you would want from a horn you might own (compromises are everywhere), and what you would be willing to do to achieve it.  It's just not realistic to expect it to be delivered in a pretty package on Christmas day.