If it is based on the basic Kar98k action design, as the FR8 and M1943 Spanish rifles are, any K98 stock will fit. The Brazilian M1908 stock fits too - this is what my bubba'd M1943 is wearing currently - though the fore-end had to be shortened to fit the M1943's shorter barrel.
I have seen pics of a 'sniper' modified FR8 on the Gunboards FR8/CETME forum. The rear sight was ground off and it had scope bases installed with a bent bolt handle. Several of these were supposedly made up by the Spanish government, and a few apparently came over in FR8 shipments.
Both my M1943 and FR8 have bent bolt handles, but the handles would still fit a scope - the curve isn't right for scoping unless very high rings are used!