As Jan says, it appears to be a 1899 carbine stock or a very well done imitation. I take it there is no sling swivel on the left side? The stock appears to be in good shape - no missing chips visible on this side. The barrel appears not to be original or at least the front sight. The front sight base does not appear to be a M1903 as the contour is different and I don't see a dovetail cut for the front sight; the blade is larger than one for a M1903 as well. It is probably a commercial base & blade. It would be interesting to know if it is a carbine barrel with the original front sight removed & a commercial band slipped on. What is the barrel length? A carbine should be exactly 22" measured with a cleaning rod inserted down the bore against the bolt face when it is closed . The sling swivels are commercial add ons.

What is the condition of the bore? If the bore is OK & the stock has no defects that are not visible, then $395 is not outrageous. As Jan says, offer less & see what happens.

Please let us know what happened!