There is a seller on eBay selling full spring kits for the 82/83 for under $30 shipped. The slide stop spring is included, and it probably wouldn't hurt to have spares of the others. Only downside is the 2 weeks to get stateside from the Czech Republic.
I'm not sure if I can link the exact listing, but if you search for "Set of 9 new springs for CZ vz.82 and CZ83" it will come up.