I would say a few hundred over the M2 Tactical. So maybe like 1400-1600. To be frank, you could probably price it at 2000$ and eventually it might sell. Values have been pretty crazy.
if your gun looks like the pictures, then it should be a Benelli USA import and late production. I like those the best, but some folks will pay more just because it has HK import on it.
These stocks have always been tough to buy, the pandemic made it worse. I think the highest we ever saw one being sold was like 1200$ on Gunbroker.
It is just how things are now. You can see the going market price of a Knight's Armament Company Aimpoint battery cap is like 200$; a little metal cap with their logo that is suppose to cost 35$. SPAS-12s are in the 3000$ and up. HK stuff is ridiculously expensive. Tons of stuff appreciated in value or selling for way above MSRP.