but then if its plated (made by plates stacked on another) file off the bottom studs and pull out the cylinder..only hope that its possible to rekey the cylinder
brass padlock instructions
1. put the lock in a vice and find the pin retainers ( round dots on top of padlock )
2. drill them
3. take out the pins
4 drill the cylinder retaining pin - there is two so watch out one is the cylinder and one is the shackle either way..it's not hard to fix
5. rekey the lock and put the cylinder back in the lock
6. add the drivers and springs
7. get some solid brass tube and replace pin and cylinder retainers
8. you may now have a rekeyed lock
*Note not all brass padlocks have pin retainers - some have bars that cover the pins - this not easily replacable..unless your a locksmith
hope that helps