HA10s are few and far between, and whilst perfectly adequate, there are plenty of other options. For example, a nice little Lentek sold on eBay a couple of weeks ago for about £60 which would have been ideal. Put a wanted on the forum and see if anyone has something suitable.
Going back to the Jelco on eBay, I noticed that the seller is selling the arm lead separately. The one he's selling will be no good for the TT2 as it is a vertical entry type. You'll need one with a right angle plug which brings the lead in horizontally.
Time flies like an arrow.
Fruit flies like a banana.