Right on, Don. Vintage tubes can often be worth more than the value of a radio, particularly before the radio is restored. I have original, working, WD11 tubes for my restored Radiolas, and leave them in the radios for display, but exchange them for fabricated replacement tubes when I want to demonstrate how these old regenerative sets work. Like many of us, I enjoy the challenge of completing a restoration that is indistinguishable from the factory original.
All the best getting the HX-10 back into shape. Do you have a Mohawk receiver to go with it?
And what is the error message you get when using your iPhone 5 on this site? We tried to design the site to work with all smartphones (I see the Forum ok on my iPhone 6s.)