The $2950 seems a little light to me...
383 Master kits with crank, pistons etc...run around $1300...then you have heads...Vortec iron sets runs around $1000, then manifolds, misc etc...plus machining, and assembly...plus core costs...
Seems very light really...
Ya get what you pay for...
Why 383...Vortec 350 will give you plenty of power...