^^^Or drill and tap for scope mount, or bend the bolt to clear a scope, or chop the barrel down to a shorter length, or replace the safety with one designed to clear a scope, or that was rechambered.
bubba guns are not a good place to go if you want original for a good price. there are any number of ways that a rifle can be altered that would reduce value permanently and and $450 is an awful high quote price, average is $250-350. even then, a new stock+stock bands, bayonet lug, band retainer bar, stacking swivel, and sling swivel plus assorted small screws comes to much more than $100, the small parts alone are $50 if you go with new repro, probably close to $100 if you go with USGI parts. so you are looking at around $600 for a gun that assuming you got a good deal and the only thing wrong with it was the stock that you could easily buy in original condition for the same price without having to scrounge Ebay for parts.