Im biased to the SuperQuad, as I sell it.
The RCA ANT751 is available at Walmart locally, but it has the lowest gain on UHF, so could be problematic.
The Winegard 7694p and AntennaCraft HBU0-22 have similar performance to each other, better than the RCA ANT751 on VHF High, and much better on UHF. The Winegard is more sturdily built but costs more.
The Channel Master 4228HD and AntennaCraft U-8000 8 Bays, and Kosmic SuperQuad 4 Bay offer the best UHF performance of the group (pretty comparable to each other and top notch available), but are slightly lacking in VHF High performance to the Winegard 7694p and AntennaCraft HBU-22, though probably comparable to the RCA ANT 751. The 2 8 Bays have a tighter beamwidth than the SuperQuad, which could be beneficial in trees. The SuperQuad has a larger beamwidth which is not really helpful in your situation as all the stations are pretty much on the same heading....but it also has a smaller profile. All of them would mount nicely on a wall facing the transmission towers without being too obtrusive.
Hope that helps...