These are high quality rifles. Yours looks to be in VG condition. At least $250, probably closer to 300.
If you decide to take it apart for a thorough cleaning, be very very attentive to each part and spring AND IT'S ORIENTATION. Some of those little parts can go back in either one of two ways, but the rifle will only function one way. Don't mix up the myriad springs. And many parts are little - I would highly recommend you set up a 'clean room', almost like an operating table, with a big old bed sheet, as some of those little parts come off on their own without telling you.
Other than that, great rifle.