I believe CRR stands for "Country Rock Regular" but I could be very wrong. Serial Number says it's a 79. It's got Dirty Fingers in it and a brass nut but that's about all I know. I'm just not sure if I should replace some parts or let it be if it's a rare jem.
I owned a '79 CRR from 1985 to about 1999; though I didn't play for many of those years. You're right, CRR= "Country Rock Regular". I have read in several places on the web that 300 CRRs were produced between 1979 and 1980. I wouldn't feel bad about replacing the pickups with something like 57 Classics. You can always put the Dirty Fingers back. I'd also change the plastic parts to black. The creme looks funny to me against those dark sunbursts. Either way, I hope you enjoy it!
PS - I still remember my serial was 71189108. For sentimentality's sake, I'd love to know where it ended up.