I can fully understand you wanting to lavish some attention on this lovely rifle, Chris.
I've wanted one for a long time and recently managed to acquire one. But yours also holds huge sentimental value.
If you're a little handy, although I've not worked on one myself, I understand that they're an easy rifle to work on. There is lots of very useful information on these wonderful rifles on the Vintage Airgun Gallery forum. Have a look on there and see if it instills enough confidence. And make sure you have those all important correctly fitting screwdrivers so as not to mark up those beautiful fasteners.
Many parts available from Knibbs, Protek and Chambers.
If you decide not to have a go yourself, I'm sure someone will shout up with the details of a suitable 'smith.
All the best,
Tone.