At this years NVCF I picked up some TR82's and a VTR103 which was in poor condition, not working, completely deaf, missing the VHF antenna and the tuning dial had been broken off. The deafness was down to AF117's, as usual, I have an antenna too.
The stub of the dial was still on the tuning shaft, but the plastic has become brittle with age and there was no chance of sticking it back on successfully, so I came up with this solution to re-attach it in a way that at least looks original.
The first thing to do is bore out the recess where the old stub was, and actually cut right through until the hole is about 12-13mm diameter. You will need to remove the chrome bright, I recommend drilling through the plastic carefully and pushing it off from the inside with a punch right in the middle as not to damage it.
Take a replacement knob, the type with what I call a 'chuck' type of grip such as seen in the picture. Trim the upper edge away until it's as far down as it will go (before you hit the brass ferrule). Similarly you need to trim back the skirt and lower edge so you are left with minimal plastic.
Stick some blu-tack on to the back of the bright, squash it so it covers it all and extends to the edges but only a thin layer. Put the bright on the original plastic knob, turn over and place the new plastic knob into the hole you drilled earlier. Attempt to get the knob as flush as possible with the original, as if it stands off then it will push away from the front of the set.
It took me a few attempts and a bit more attacking with the dremmel and wire cutters to take the plastic down far enough. Once you're happy with it, mix some epoxy and allow it to run down the sides. Once it's almost set, place it on a shaft such as a spare volume pot and make sure it rotates without wobbling off centre, if it does, push and hold until the epoxy sets (I used 5 minute epoxy, works fine here).
Lastly, attach to radio, tighten the chuck grip, then attach the bright using a drop of glue or perhaps even just blu-tack (it can be fairly tenacious!).
The end result looks original and means you don't have to risk smashing the dial to get it off next time.