Hi Pete
Those sewing machines are beautiful, evidently built when manufacturers cared about the quality of their product. I had the pleasure of working on a late 1950's Singer portable 185J a few years ago (please excuse the clutter on the table). Having typewriter covers made for servicing and reconditioning those sewing machines sounds like an excellent trade. That's what I would call complimenting each other's skill sets.

We humans go through many computers in our lives, but in their lives, typewriters go through many of us.
In that way, they’re like violins, like ancestral swords. So I use mine with honor and treat them with respect.
I try to leave them in better condition than I met them. I am not their first user, nor will I be their last.
Frederic S. Durbin. (Typewriter mania and the modern writer)