I recently purchased a mossberg 500A with wood stocks, two barrels (18.5" & 26") and a pistol grip. I paid $319.00 for the gun and I wanted to replace the wood stocks with a set of speedfeeds. I ordered them and the forearm doesn't fit. Apparently the sction slide assembily is shorter on the 500As. Any advice on finding a matching forearm that matches? I'm also considering selling it. It's only had 15 shells shot through it. If I include the barrels, speedfeed stocks, pistol grip, and gun case any ideas on what might be a fair asking price? I was hoping for around $300.

Have you thought about trimming the forearm?  What about this?

If not, what SP stock do you have & how much?