yes its for sure ss. the first pic I put up showed the rune. some people said they cant see the pic though. you can kind of see it on the barrel pic there on the bottom. yes the first guns the Israelis got were in 8mm and then converted in I think 1951? i found this one on the EE. he has another for sale you can check if he still has it.
I actually have one in 7.62mm- fricken laser beam. That totaly looks like a SS rune on yours. Nice find.