Sierra from 1987 to 1990 have the same locks. Post 1990 have no fuel cap lock and the boot lock is different.

1661661 is the finis number for the lockset from Ford as well. Only about £50 last time I got a set.

You can also just buy rebuild kits as well for each individual lock and build them to your key number if it is only 1 or maybe 2 locks.