Mike,
Bulgarian P-08 are commonly found "sanitized" in a manner similar to yours. That is, all the markings which might betray its origin--either as an "Imperial" weapon or an Eastern-bloc weapon--are removed. There are two predominate theories for this: that when Bulgaria was taken over by the Soviets all the markings which betrayed a Monarchial connection were removed; or markings which identified it as a Communist country of origin were removed in order to import it into the US. Each theory has its adherents, and there is insufficient documentation for either. You can find a useful discussion here
http://www.gunboards.com/luger/topic...erms=bulgarian on Jan Still's Luger collectors' forum.
Theres no telling how your Luger might have come by its stamped toggle train.
These Lugers are scarce, and it appears that yours is sufficiently authentic to take its place in a non-shooting collection.
--Dwight