You'll have to be pretty dedicated to get these if you're going to solo the mission they are from.
I remember farming these before I transferred my file over to infinity and I admit I couldn't clear that run as RA solo =.=. I needed at least one other person to help me with it. And doing it as Beast RA? Beast pp regen was so bad I never tried it. I'd use either Newman or Cast for farming C2 as RA.