Not sure one what kind of trans you can get for $2500, but you can get some good trans parts. Maybe a BTS, JW, or Racer X tc and vb to start with.
Or rebuilt stage ones-$1200
T500-$450
6.0 trans cooler - $100-200
7.3 or 6.0 IC- $100-200
E99 spyder- $100-150
Pipes- $200
IC boots- $100
Reburnt...