I just kept searching and waiting for a carpet tree on ebay (nothing good here, they're all wobbly and weak-looking), and finally found one that I bought and am happy with. I think I paid a total of $255 (including shipping) or so. There are better deals out there, but I think the price matched the quality of the tree. It still looks newish (the layer of cat hair effects the look, lol) and all three cats love it. Willow all but lives on it, Buffy exercises her nails on it constantly, and Molly loves sitting/laying between the legs on the bottom, hiding in an open way, lol.
Check ebay, a lot of trees sell cheap (the one I got started at a dollar, I think), but if it's good quality and the seller has a good reputation, other bidders may drive the price up. Just keep an eye on the shipping charges, as 70lbs by mail can be pricey, lol