Having done a bit more research, it appears that there are some hardy and large Borindas. I see some suppliers are claiming that Borinda perlonga and Borinda papyrifera are as hardy or hardier than Thamnocalamus spp. Whitelea Nursery are claiming that Borinda grossa is both truly enormous and very hardy; and they have several others that are both large and hardy, including one they informally call "giant Borinda". But all are likely to be expensive and very limited quantities available of all this, and will probably need a lot of water to grow well.

I see also that Fargesia utilis is claimed by some (though not others) to grows up to 6m, though as it is scandent (bends over) you'd need some wires to keep it upright. Whitelea claims the little known F. yulongshanenis is taller.