I assume you mean the 4-16x50 Klassik. A very nice scope. The resolution and contrast are excellent. The A8 is a heavy plex reticle design - not my first choice for long range. if you can get it a good price, it would be a fine scope to own, even if your son eventually switches to something with a milling reticle.
Any quality Picatinny base and fully machined tactical rings would work fine. Leupold, Nightforce and Seekins are good ring choices. There are several others.