Ergodox[0] provides split keyboard kits. There are some boom-style mounted monitor workstations vaguely in the vein of the NovelQuest Emperor[1] but I have yet to see one at a remotely sane price point.
I also haven't seen the monitor mounts discrete from built-in seating, though it doesn't seem outside of the realm of possibility. One could realistically place a large A-frame styled wooden structure over a La-Z-Boy chair and mount generic monitor arms onto it via clip or screw.
So, the main challenges are just carpentry and cable management.