It's rare for one of those switches to go bad, but 2 of them? As long as the switch has been soldered correctly and the knurled nut is kept tight you really should rarely if ever have a problem with it, Many LP's from the 50's still have the original switches. Just about any music store should carry a quality switch of this type, if nothing else, Gibson has it's own line of replacement parts, shouldn't be hard to find. My question is whats going on here thats causing these switches to fail? Have you ever noticed the switch being loose, flopping around inside the body loose, or the nut needing tightened often? You said it had to be resoldered once, any idea what caused the connections to break? After you get it fixed, I would take a hard look at what is going on outside the guitar.....