WTB 700c rear wheel, flipflop or fixed

My son's rear wheel was stolen while his bike was locked to the rack at his HS today.  That's the third theft from those racks our family has had; the other two were whole bikes.  But that's another story.

I'm looking for a replacement wheel, as noted above.  The previous (and match to the front) was some kinda generic black deep v style rim, no-name flipflop hub.  A very nice 23mm Gatorskin was on it.

Bike thieves suck.  Son has now had two bikes and two individual wheels stolen in less than eighteen months.