Best thing to do is ask at your bike shop. I got a Mavic Open Pro on my bike which had a similar issue and it's been good. A decent prebuilt wheel should be around $100.

Not all wheels are compatible with your bike either. It shouldn't be a problem to find an 8 speed wheel, but many modern wheels are not compatible with 8 speeds.

Switching the rear wheel is also significantly more technical work than switching the front. In addition to changing the tire and tube, you also have to move the rear cassette (which involves tools) and adjust the derailler.