Nice score!
A friend of mine gave me a TUG-8 with D104 head a couple weeks ago. He had a dozen or so that have been sitting in a cabinet not being used. First one I have ever owned, and I absolutely love it.
The handheld D104 mics definitely don't sound like the TUG-8. A CB friend of mine has a D104 hand mic, and when he plugs in his TUG-8, the sound is a good bit different. Sounds better to my ears than the D104.
The TUG-8 I got was not rusty, but it did have very light corrosion on the chrome head. Bought a can of Eagle One Nevr-Dull wadding polish, and it's now gleaming with a mirror shine. It looks new.