Luger Questions

About 5years ago I bought a luger for $299 which I thought was a good deal it came with an original almost excellent shoulder stock, but not correctly numbered to the gun. Whats it worth?

Now on to my other questions, the Luger has an unmarked 6.5 inch barrel, all numbered parts, trigger 72, firing pin toggle 72 also has a stamp that looks like a man with his arms in the air surrendering, barrel release lever 72, frame 772 over h, and wooden bottom on magazine is marked GL over N over 772, on right side of barrel frame is a Crown over an N, no date on top, and the side plate has a Crown over a B original gold colored handgrips.

Now the part in question, and I don't know if it is original or correct is the top of toggle which is marked with only byf and no other numbers, is it the original Mauser toggle strap, or is it a replacement, if so who is the original Maker of this Luger, ERFURT? DWM? byf? and about what year was it made. Whats it worth? Thanks for any help.