I have both a TN 30 and TN 40 that I use a lot. Both reels are in great working condition but it is increasingly difficult to find parts for them. I need a new handle assembly for my TN 40 and find none available. I ran into the same problem with my TN 30 but found the handle for the new Torium HG will fit the TN 30. Is there any other handle option for the TN 40?
Numerous rees use the same diameter drive shaft, so you will get others to fit.
There are many aftermarket handles and knobs available, you can search around this site as well.
Part availability has become a big issue for some older reels.