Welcome to the Forum, and yes , as a rule any add on things to any gun are not going to get their true value unless as noted above, they were "possibly" factory offered, and the gun is in awesome shape, has the box and all, the shipper, ,everything,THEN by all means it is a sum of the total of the parts, and you'd get TOP dollar, BUT normally this is NOT the case, it is "added" on, the condition of the gun is "normal" (average) and the grips are just that elephant ivory, and as such what the market value may hold for them.......if the gun is "average" shape flatgate, in the serial number range you cited, the gun is slightly more worth than the grips,,,I would sell them separately, IF this is the case...........if the grips are NICE, fit the XR-3 frames "well", and either have medallions or not will be somewhat of a difference...ivory grips are in the $400-500 for plain, GOOD fitting, nice "grain" in the ivory........then again, one never knows, a lady recently sold her husbands flatgate Single Six and it had factory stags grips and she got $250 for it, and she KNEW what her old man had paid ,years ago, for the gun, and the grips and it was less that $100,so she was HAPPY !!! :shock: sad really, as she gave it away..........yes, I offered the buyer 3 times the $250, and he just smiled....... 8)