I agree with the advice to save the Tracey Body..........You may want to call Mike at Classic Glass in Rockton, Ill. 815-624-7831 Mike makes tanks and seats from vinyl resin. He can repair your fiberglass and properly line the tank. Or, he could use the entire unit to make a new mold.
A Tracey was recently offered on ebay and apparently a few more have been located. Prices are a little soft but tend to be in the $700 range.