I doubt that particular Unertl scope model is woth more than $400..
Havng said that, so is the rifle itself..
At $525 ,it sounds like a good deal:)
Sold listings on ebay show otherwise regarding the scope. I've been watching for a while and if in decent condition the minimum is $450 with the higher power ones topping out at $1k. the 6 and 8 power are very popular for replica sniper rifles and bring a premium. Just the mounts by themselves sell for upwards of $400. Right, wrong,or indifferent it is what it is.
