Don't do that, you end up paying double. These stocks aren't cheap anymore, you're looking at about $200 just for a stock these days. Make sure you are happy with what you are getting, don't plan to improve it later.
The thing with linseed oilon an Arisaka
finish is it just provides a bit of a shine to it and will darken any scuff marks. It can't penetrate the original finish and won't replace it where it exists. I oiled mine just to get the grime off of it and it shined it up nice but did nothing for the roughness of the stock.
Finish on this could very well be fine. One reason I prefer buying in person but I have gotten a few off auctions. Don't forget the shipping fee and the transfer fee if required where you live. This may have to go to an FFL dealer for transfer to you.