Not to disagree, however I will throw this out there... I can't be sure how the top figure is defined, but it did strike me as "possibly" a M/Anchor and that is sometimes seen on G98's which are assume RM (navy) service (usually builds), but so far i have not seen this marking on a bolt lower flat. It is sometimes seen on the barrel and or receiver, though there are several forms of RM proofing and acceptance in the interwar, possibly early national socialist era.
Maybe tighten up the picture if possible, I can't be sure that is an anchor under the "M", but if it is maybe there is a correlation. Anyway, just a toss out to confuse or possibly stimulate the discussion!
** Yes Bill, I received a lot of good deals starting out from you largesse! I also remember those early Turks and the value they had in parts, armorer spares and rods often made them worthwhile.. a couple nice ones surfaced too.