I suspect taking a stock to an automotive or motorcycle painting specialist might get you good results, but perhaps at a higher price than you might expect. Or, if you're unlucky, the results might be disappointing, especially if you go for the lowest bidder. Applying primer, sanding the stock, applying paint, and finally clear coating along with all the associated gun cleaning, mixing, solvent disposal, etc. takes time and if a company is not set up to paint stocks on a regular basis, a sane painter is likely to ask a significant fee.
As an alternative, consider people who finish stocks all the time. I recently sent a primed and sanded McMillan stock to Tactical Graphics in Melbourne, Florida for a hydro dip job. They put on a two-tone base coat, hydro-dipped the stock, and then applied a glossy clear coat at a good price. Base price for a stock is a hundred bucks, but since mine had a cheek rest and I wanted a two-tone base coat, the cost went up to around a hundred and a half, which, as someone who used to paint a lot of cars, airplanes, and boats but who has since sold all his equipment, I consider this to be a real bargain. Plus they had a very quick turn-around and are nice to deal with to boot.
So, if you like the idea of a fancy design, think about hydro dipping. Here's my "Alligator" F/TR rifle.
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