Your Globeco .303 SVT has been heavily modified already. It there are two little slots on the sides of the receiver you can use a proper SVT scope mount. Otherwise I'd agree that a side mount properly screwed to the sidewall is a good compromise. There are a lot of Moisin Nagant style sniper rifle bits and pieces in circulation, that you wouldn't be insulting history THAT much. Russian aftermarket scopes and bases on a modified Russian rifle.