Having an SKS in modern conflict, I mean full scale civil war. Probably wont need to clean it much because person using it wont last too long if they are actively partaking in said conflict. Oil of any kind will do I think. Speaking of another possible issue called mechanical repairs - pair of priers and a multi tool will do. Personal experience. I had one major failure while shooting on my friends land. Rear of main spring popped behind the piece that holds it under pressure, rifle kept going for a couple of rounds and chewing that spring until rifle stopped functioning. Took it from the our firing line, opened it up, couple of coils got mangled. Took rear spring assembly apart, used a pair of pliers to cut damaged rings off, put it back together, went back shooting. That was probably 5-6 years ago. Never had to buy new spring. Still have that rifle, still works. Run of the mill bubbafied Tapco SKS, my regular "shooting gun". Thousands of rounds down the bore but I do take care of it and it only failed that one time. It's still alive.