There are strap marks on the back of the 1976 CWC from nylon NATO type strap (the leather is none original).
Timefactors natos are the softest and most comfortable if you need a replacement.
http://www.timefactors.com/natostraps.htm
The Hamilton doesn't have wear marks, so it would be a shame to scuff it up now.
A new leather strap on the Hamilton would give you two very different looks for each watch when you wear them in rotation.
You are going to need an open ended Bund, or Aviator strap around 18-19mm wide.
http://www.timefactors.com/tfstraps.htm
PS - leave the lume alone.
Once it's gone it's gone forever, and the watch is none original.
If you need lume, by a new one.
Same with the acrylic glass. The scratches might polish out, allowing you to keep it 100% original.
They both look good just as they are.