So I have a 1991  mr2 GT.
The problem is the previous owner has lost the boot key, 
and it seems the boot cable has detached from the mechanism.
I can get a key cut for the boot if I know the lock number.
Is there any way to get this number without paying a locksmith $110
to pick the lock?
Cheers

What about buying a used lock and key? Should be cheap as if its an early model as people have them left over from late model tail light installs.
Then just get a drill and drill straight through it something. Or bash a screwdriver through it.