This tutorial answers how to get spares level 3 for repairing the saiga 12 on sZone-Online PC Game.
You have to disasamble a level 3 weapon. i tink the cheapest lvl 3 wepaon is the deagle.
You can't disassemble a Deagle to get parts for your Saiga. Pistols are secondary weapons, and use other parts than primary weapons (shotguns, rifles etc).
I believe you can disassemble the PPS-41 however, and get level 3 parts. Note that the success rate is low, and it's somewhat expensive to even try, so you might be better of buying the parts if you find them cheap.
Both to disassemble and to restore your saiga, you'll need the appropriate skills. Consult a craftsman. If you're on PvE EU, ask Rafaellus, and tell him Vasiliev send you. He's a clanmate of mine, and the best damn crafter I know.
Yes it works, i know the game used to have pistol spare parts and rifle spar parts. but the saiga needs a weapon spar part lvl3 and you get a weapon spare part 3 from a Deagle i've tried it a few days before and restored my saiga with them.
Edit: if your eel suit has less than 70% just go to a work bench you'll see what you need. but the sate has to be below 70%