I can easily spot bullet holes in paper at 100 yards with all of my riflescopes that top out at 8x or more. Any current spotting scope will likely allow you to do the same.
That said, for an inexpensive range spotter, I've had good luck with Konus. I've used it to spot shots on paper out to 600 yards. It may go farther but I've only shot steel past that.
