After some guessing and trials it appears that the marking in the cutout for the frog (of the sling) reads "DRP Ldsht" for "Deutsche Reichspost Landshut". Landshut is in Bavaria and nearby Munich.

It is a big pity this rifle was sportered, it appears to have been in nearly unmolested condition since the DRP marked rifles generally did not see the heavy service military rifles at the front were facing. The front sight appears only to have been slided on and maybe glued or soldered in place (probably also screwed, maybe if you pull out the blade you'll see a screw right below it). The stock was cut at the very rear position and therefore can't be repaired rather invisible with a duffle cut (which is a huge pity, given the nice cartouche it has on the stock).

On the one hand you have a rare rifle in very nice condition which would deserve to be restored, on the other hand so much was destroyed in sporterizing it that it never be what it originally was. Restoring it will take high effort and a very good gunsmith, and still you will only have a restored rifle. Plus it won't be matching again. I don't know how good you are at restoring nor how much time and patience you have in finding the correct parts, but if it was me I would rather sell the rifle.

Maybe the guys over at k98kforum.com can give you a different input, but this is what I would do.