OK, I just measured it at 135mm, and also noted that the 7 speed gear cluster is a cassette not a freewheel, so one less thing I'll need to buy. Performance has a rear wheel with their own brand (Forte) hub/rim and a rim-brake comparable rim for $70 on sale. I'll either go with that, or a Sun/Deore combo at Harris for $150 (two wheels).

So it looks like I need to buy

*wheel
*rim tape
*4.5mm spacer.

Thanks for the replies