Welcome to the forum.
Does just disabling the touchpad not work for you? Looks like it can be disabled in windows. But be sure you have Framework’s drivers installed, otherwise you may not have all settings available [RESPONDED] Jumping - Disappearing Cursor - Track Pad - #9 by MJ1
Framework has not mentioned plans to create a blank palmrest. It’s possible that someone from the community could create a 3d printed one.
@ mods, perhaps merge this thread with Option for no touchpad?