The sliding door locks were made by Schwepper [ https://www.schwepper.com/en/ ] who have been *fairly* helpful when I’ve enquired about getting extra keys cut, but I ended up getting similar ones cut closer to home by Steve, the boatbuilder, at Ramsgate harbour.
If Schwepper can’t supply IDENTICAL replacement locks, they can probably supply SIMILAR ones (slightly more recent versions).
When I needed a key, almost every local locksmith that I asked was unable to locate blanks. (And tHere are a lot of local key shops and locksmiths in metro Detroit). Then the starboard door could be locked and unlocked only from the inside.
Fred’s Key Shop, on Second Ave.,in Detroit, Michigan, had the blank and had a guy (an old, old school locksmith) who fixed the lock mechanism, quickly and correctly. The cost was nominal, with no “marine hardware” premium.
Sourcing parts, services, and craftspeople to fix and refit a 32 year old boat has led me to stranger places. Good luck with yours. Hopefully you too can find a local old, old school locksmith. And there is always Fred’s.
The Boat of Laughter and Forgetting
1989 Nauticat 33, HN 1072.