Definately an RG built from 1987-1993.
its a 570 if it doesnt have a pickguard, and is HSH.
Its a 550 if it has a pickguard, and is HSH.
My guess, since its rosewood, is that it is a first year 1987 model, and the serial numbers on those were on little silver stickers on the back of the headstock (which you could peel off, and somebody probably did) It will have the original EDGE tremolo, and a WIZARD neck. (not super wizard, what makes a wizard "super" is the bubinga skunk stripe on the back of the neck, which they started doing sometime after 1993)
How much did you pay for it? (if you dont mind me asking)
I found a 1987 RG550 in black at a pawnshop for $100. . .I thought it was FUBAR but all it needed was some deep cleaning and it was good to go.
GOD I love pawnshop surprizes like that. My bud found a 1992 RG560 Guitar Center 27th Anniversary edition at a pawn shop for $100 too, he painted that thing bright green, sanded the neck, scalloped the last 4 frets, and cut a monkey handle on it, and its the best playing RG ive ever laid hands on!
Got any pictures?