Difficult to have an opinion on value considering you are in Europe, here it might be worth more to a specialist collector, - someone that knows the difference (and cares), but most probably do not collect sub-variations and yours is a sub-variation of a sub-variation, meaning it is a type 1, second type (
without the siderail designation, most type I have a siderail designation.)
That it has been re-barreled and re-stocked will influence value significantly, the stock more than barrel, as at least the barrel is period. It is a fact that early 98b's are far more rare and elusive than later blocks, generally up to the b-block they are very difficult to find anywhere near matching and original. c-d blocks are tough too, e-f blocks are most common, especially in matching condition. So you have that going for it, very hard variation to find and the bolt body and TG is original (
two damn difficult parts to find for such an early rifle); maybe in the US in the $700-1000 range, maybe more if you can find the right buyer. Most wouldn't know or appreciate the difference between the variations.
There is no registry (database) on line, Volume I of Mike and Bruce's book probably gives the best outline possible, I am not sure what breakdown Mike used off hand, I told him how I have broken them down, but i think he went his own way, as I am sure Mark Wieringa also has another method. I assume other researchers are out there that specialize in the 98b, but as they are private their opinions and database is unknown (
and insignificant, information held by one man is meaningless if he keeps it to himself... to an extent everyone keeps hard earned knowledge and research to themselves, but at some point it only has value if it is utilized in a manner that others can see and evaluate it. There is not a shred of doubt that extremely knowledgeable collectors exist, probably know more about their specialty than Bruce, Mike, myself, etc.. but as they, and their work, is anonymous, they are irrelevant unless they share what they have learned because it will die with them. That is why Mike and Bruce's work is so important, - Mike and Bruce have given specialists an opportunity to make their research matter...)
The Kar.98b, in all its variations, were probably made from 1924-1931, going by my research, this rifle would probably be a rifle made in 1926. Before the IAMCC departed, but after their influence was in decline; the maker was Simson Suhl, but it was certainly reworked at a depot, probably twice, once for the upgraded RS and again for the barrel. Surviving rifles is impossible to know, but probably only a couple thousand at most of the approximately 70,000 made, most in thoroughly mismatched condition. Probably half known came out of the Albanian imports of the 1990's, which were thoroughly mismatched, though most did have some original parts. The 1924 I own is one such rifle, from the imports that came in from Albania.
Thank you for info Loewe, it´s really interesting. I would like to know, how much can it be worth, I´m not going to sell it anyway, I´m just curious. Is there a registy where I can study numbers, how much of these rifles were made in which years, with which serial numbers etc? Who has made this particular rifle? How much of G98b rifles remained till now?