So is that a left handed walnut stock for a right handed bolt action rifle?
As a leftie I am always on the look out for left handed rifles/stocks, but choices are limited. So your LH stock would be of interest to the likes of me, but I presume that there are not all that many Sako A1's out there in the possession of lefties so demand might be a bit low.......not sure, just guessing.
I tend to price things cheap when I sell, can't be bothered waiting ages for them to go, if at all. So I'd say min £150 to sell sharpish and up to to £250 if you can be bothered to wait or possibly a bit more if it really is a nice custom stock and you can find a keen buyer. Look at Guntrader and Gunstar, or even Evilbay, all have stocks for sale and you'll get an idea of prices off there.
I managed to buy a SH LH McMillan for my Tikka 590 for £225 - took years to find one admittedly!
Best of luck with the sale if you proceed with the deal.
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