The thread count is pretty unique (for going into plastic), that's why (IMHO) they're going to be pretty hard to find at a Home Depot/Lowes type of store.
Couldn't hurt to bring one over and try to make a visual match, but (again IMHO) you're probably going to just be wasting your gas & time.
Hey Mike.... what was this Google you spoke of earlier? :lol:
:roflmao: