I would steer clear of that one. It's a put together. There is no way that rifle was originally in that stock. The metal surface is all pitted and has been reblued. Bolt on the other hand looks like it's supposed to. Early Arisakas are very nicely done, smooth bright metal, etc. The original stock would be beat to crap with a metal finish like that. I'm not an expert on telling the difference but monopod is probably a reproduction. It does fit correctly and no extra bump on the wood I can see so it might be original. Just thinking odds are against it. As for the bore, It should be bright as these were chromed. I see no evidence the chrome is left and "dark spots" in a chromed barrel doesn't sound good. Stock has been varnished according to the seller so even that isn't correct.
It escapes me why anyone is bidding that one so high, it's a representative place holder until a nice one comes along. Considering with shipping it's already at $395 and there's going to be a transfer fee on top of that, there are a lot nicer rifles around for that kind of money that have mums, actual original finish and are matching.