Re: M48. Worth the price?
If this is, indeed, a "New, Never Issued" M48 with all matching serial numbers, it might well be worth $399.....but it would be a terrible shame to "bubba-ize" such a firearm.
Back in the '50's when you could buy excellent 98k's for under $15, and there were tons of them on the market, perhaps there was an excuse for doing such things....but not any more. WWII military rifles in their original configuration are getting scarcer and scarcer, and many types have reached "semi-historical" status.
If you want to "sporterize" an M48, look for a used one with a nice action and bore. Lots of 'em out there for less than half that price.