Is it the ignition lock barrel or the electronic portion? The latter has two small screws holding it to the back of the lock and gets crudded up over the years. You can open up and clean/grease the contacts.
The ignition from an early pre-facelift Euro Capri Mk1 will fit (it won't have the key in seat buzzer connection), but those cars are getting rarer and the ignition locks less
I believe an early Mercury Capri lock should fit. If it is just the key barrel, I'd take it to a locksmith and have him re-key it or put in some new pins.
Larry Finch (LF-TP 2511 username here) usually has the electrical portion and maybe even an ignition lock.
Julian
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