Boyds and Richards are 2 of the biggest makers. Boyds has mostly drop-ins and fully finished. Some custom stock options as well. If you want to do the finish work yourself, then you might want a Richards.
I did a quick search and found several who advertise custom stock duplication. Most look like custom gunsmiths. One called Custom Stocks and Steel listed some pricing (customstocksandsteel.com). Richards looked like they had the widest selection of patterns. I also spotted an interesting facebook video of a stock being duplicated by a custom shop that is pretty interesting to watch.
It has been a long time since I bought a stock - I think the last one I bought came from EC Bishop and cost me about $39. What kind of gun is this for?
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