Seems like neither solution will work.  It needs to fit within the same space. so it could be the same size or smaller. and it needs to be command compatible.

how about other modules that might be New Old Stock.
Or
Is there anyone out there perhaps selling a NOS module?

Thanks

I'm looking for a replacement for a GU256x64-312
send me a private message if you know a source.

does anyone know a compatible module, It doesn't have to be VFD and doesn't have to have the pin locations exactly the same, as long as it's about the size and command compatible.

Thanks