Ther RA65 specifies leaded for the RON, rather than the lead. Leaded was 96 RON, premium unleaded is 95 & regular unleaded is 91/92 IIRC. You might get pinging with regular unleaded and have to play with the timing.
My car used to be a lot happier on leaded/LRP, but these days now that it's tired, I'm not so sure.