Gearbox Problems HELP!!

Hello i have a twin turbo 1990 gto. My clutch was slipping a while back and i upgraded the exhaust line to full 3 inch whiles the clutch still was slipping. Then the clutch was completely finished after this upgrade and the car would not move. I purchased a new clutch and durng the transfer of the new clutch which was 6 puck extreme plate clutch kit i noticed that piece of the shaft in the gear box broke into the transfer case. The piece that broke was about 3 inches long. what should i do can i convert the 4wd to frontwheel drive?? cause over here in the bahamas the gearbox is really hard to find and to bring one would run me into about $5000. what should i do ?? i really need HEEELLPP!!