I have a vt320 here, getting the roms out to dump those looks to be a gigantic pain in the ass, they're in a metal cage which seems to be soldered to the pcb, underneath the tube.
I also have a C.Itoh CIT-220+ which looks like it might be using stolen vt220 or vt320 code, unclear. It uses some very odd chips for graphics control, though everything is standard JEDEC ROMs for actual character sets, main code, etc. I have it fully dumped, including the keyboard MCU. (and I have to thank Kevtris for desoldering all 125 keys from the keyboard in order to facilitate repairing it, which is now done. Someone had spilled coffee into it years before I got it and it wicked up into the key contact leaves of most of the keys, so pretty much nothing worked) The C.Itoh keyboard is far more repairable than the LK201 is (usually lk201s get scrapped when they die because the membrane goes bad) and uses real spring+leaf switches for the keys rather than a membrane like the LK201 does.