Hi,
Long Answer:
I'm no expert at tools and toolboxes like you guys. I got lucky and the last old Snap-On tool chest I got (1980's vintage) came with a working key for the lock.
However decades ago, I found an old Yale padlock that I loved the look of. I have no idea how old it is except that it's at least 20 years old now...
Needless to say, there was no key and no one knew what to do. I think I found it at a swap meet. Somehow an extra cylinder fired up in my brain and I took it to a local locksmith shop. They said if it's not a block of rust inside, no problem. I came back a few days later and this ancient beauty now has a working key.
I just got another vintage tool chest (I think from the late 1940s - early 1950s) that does not have a key as I recall. It's being shipped and now I don't remember. If I keep that one I'll remove the lock and take it to a Snap-On dealer or the local locksmith to have a key made. Then sell the 1980s one.
Short Answer:
- If you don't go with that "thumb latch", which does seem like a good idea:
• Remove the locks and take them to a local locksmith shop to see if they can make new keys for them.
• Maybe you could also simply replace the locks with new locks & keys that fit the socket?