Alternative to padlock?

This question has probably been asked before; I just couldn’t track down the right thread: Does anyone know a solid “after market” alternative to the padlock found on metal cages? The standard padlock used in many cages is problematic because it’s bulky and tends to rub against my partner. I really liked how the Holy Trainer V2 hides its lock, so I’m hoping for a similar compact option that can be added later using a key instead of replacing the existing one. This would replace the need for the threaded pin and security screw combination available on custom devices. I know you can buy security nuts and screws separately, but I haven’t found a set with a unique key specifically for those screws. A mini-cam lock about the same size as the “magic lock” used on the HT would be ideal. What do you think? Robert

Oops! I had too many typos entering this post on my phone. I’ll repost the question properly later, sorry!