I wish chis immel was still around, he'd know all about it.
Who dares summon me from my slumber?
Oh, it's you.
Well, I don't know all about it, but for what it's worth...
It's an odd one, which makes it harder to put a location on, but, I'm thinking more southern than northern.... but that's hard to say. Maybe somewhere along the Main, but that's a total wild guess. The carving looks more southern than northern Germany to me, but that's just a feeling. The gun has a lot more drop at the heel than normal, which also points south... in a manner of speaking. Apparently, the stock was originally not nearly so fish-bellied as it is now(?), at least from what I can see, so imagine the gun with a fairly straight line from the wrist to the toe, and the gun starts looking much more normal. Date... that's about as difficult. I would personally say last half of the 18th century.... pretty broad. But I would think probably a little closer to the end of that time period rather than the beginning. The lack of a buttplate makes me think later too. You see rifles with heel plates (not full buttplates) starting about mid century or so. This one just has a heel screw. Oh, it appears the sideplate panel has been seriously leveled off. The little teardrop sideplates may well have been added later. They do look seriously out of place.
Just as an aside, when I saw this gun, I immediately thought "RCA 15". Not that I think the same person made this, but notice some of the features. The drop at the heel. The way the nose of the comb is shaped (kinda fat and not hollowed out or cut in on either side). The heel screw. Just... interesting.