Sup

I have a 1998 Z28 and about Two week ago my clutch went out along with 3rd and 4th syncros. I took it to a transmission shop to install a syncro kit and a clutch. These guys from the transmission shop were trying to charge me $2000 for those parts after they dismantled my T-56. I then went home to look up how much those parts were and they were nowhere near $2000 dollars. These guys charged me $380 for the dismantling and for the inspection. These guys are obviously trying to charge inflated prices. I am now in the middle of filing a complaint with the BBB so this shop is recognized for its inflated charges. These guys from the transmission shop rebuttal were focused on how uncommon these transmissions are and how hard it is to get parts for them. Can you guys help me out with a response to how common these transmissions are?