i'm sure you can find a pitts bipe on ebay for sale. i think there are few of them coming out of China these days. i don't know much about the quality but it looks fine.

as for me, i've got the WM Ultimate 40S and have owned the WM Ultimate 30. The 30 was an awsome bipe that tore up the sky with uncanny precision yet rolled and spun with the best of them. The 40S is still NIB. loved my WM bipe with the original Blue Hawk Red White and Blue and prefer that over the current TOC covering.