I gotta go with JK on the S/243.
The S/243 just does not look right.
No 98ks were made with grasping groove stocks.
Here is a photo of a 1934 Banner rifle to compare the groove.
I would have real concern as to originality of the stock given the length and location of the grasping groove.
GEW98 stocks were re-worked for the 98k. The stock would then bear War 1 proofs or evidence of scrubbing. A photo of the serial number on the toe with the right side markings might clear that up.
Another 'alarm' would be the rear sight top being blued. In 1936 the sight top was polished bright on all rifles. On a 1936 S/243 rifle, ALL parts big enough to take a stamp are numbered and most are either droop or stick eagle 211 marked.
Here a couple of pics with what you should see from my 1936 S/243.
The dot looks straight from the one photo. Can't tell from it if the stock has been refinished or polished.
If it is all matching original finish otherwise and given the relative common code/date, I could see it going for 7 plus.
Maybe more, but only with lots of detailed photos including the serials inside the stock and handguard along with bolt part pics.
Value on the 36 would absolutely hinge on originality and again, without more photos, there is no guessing.
My take, JT