I’m with you with the cost: I don’t think it will be easy to find a couple of grips with fascio for less than 200/300 euro; about the theory of RSI era replacement, I’m sceptic: the hated symbol was the royal crown, not the fascio. It is possible instead that replacement was made soon after WW2, when all the fascist symbols were at least politically incorrect, if not illegal. Or simply broken and thus replaced, being bakelite quite fragile.