[DeTomaso] gas tank advice needed

[Christopher Kimball]

More unfortunate news concerning the car I just bought (1972), the gas tank 
has a slow leak, so with the generous help of Mike Thomas and Gary Herrig we 
pulled the motor and tranny to remove the tank.  Performance Radiator in 
Tacoma, WA cleans, treats, fixes and then coats tanks and, in fact, just did 
a Pantera tank not too long ago.

I took my tank to them, but just got a call informing me there was a bunch 
of JB weld on the tank, and when they scraped it off, the holes they found 
were "significant."  Although they said they could still fix it ($325.00) 
they said due to the difficulty of removing the tank, I might want to 
consider other options, such as replacing it.

My survey question to you all is:  should I have them repair it for $325, 
buy a new tank for I don't know how much, or try to find a good used tank?  
The risk I see in buying a used tank is that since it will be 35 years old, 
too, to be safe I'd probably want to have it coated anyway, which might make 
the cost not that much less than just buying a new one.

What do you think?  (thanks for your help).

Chris