by 'open loop' on the pick-up, i'm assuming the windings, so it's either done for or a real tedious repair.
finding original T-40 stuff is difficult & becoming expensive. i have some screws that can be used - what i've got were bought at a Boat store, they're not exact, but really close, you can't see the difference when screwed in, but in your hand the ones Peavey used have the more flush head that instrument makers use to hold pickguards on, while the ones i got have a slight countersink, to hold stuff to boats, naturally. i replaced around 8 rusty ones on my bass, they look fine and will hold up at sea.
i'd be glad to mail a bunch to anyone that might need them for nothing, PM me, i'll check back later