Friend of mine in Finland has a JPS&S SxS 16 gauge shotgun and he's looking for dating information, JPS themselves weren't of much help.
It's a JP Sauer and Sohn Suhl 16/70

Proof on the top of the barrel is "Special gewehr [4 rings] lauf stahl SG1". Thinking it's a latter 1950's shotgun.

I'll post pics if you guys need them