Ike,
The gun shop should be able to release all the items to you, right away, except for the gun.
The $ 2000 spent is probably in the gun-value if original finish, etc.
The accessories (leather and stock) are just a "throw in" as part of the deal. So not to fret too much about those.
Some better photos of the wooden shoulder stock would help our Artilley folks see if that is an original piece or a repro, too.
The two black bakelitte magazines are not WWI-era but from WW-II...Mauser Luger magazines. Probably $ 125 or so each in that condition.
I have moved your photos over and lightened them up a bit so our Artilley folks can advise you more on the pistol.
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