I got hold of the TT ones second hand, and cheap, as I needed the failsafe of a second light in case a bulb blows at night.
Of course to discover they dipped the wrong way. So I managed to remove the actual lights and replace them with 100mm VFR400 lights (If I remeber correctly), and sandwiched them in between the TT plates,made up myself a double wireing harnes and plug into the exsisting light socket.
They give decent enough light (with twin 55w 50% brighter bulbs) for dipped riding, But I still added added extra spots for night riding, which I do a lot off especially in the winter.
I did first worry that running two 55w bulbs would melt something, but when I checked the TT catalogue, these lights cam with 2 x 55 bulbs so was satisfied, 6 months later, and after running the lights on every day and night, I haven't had a problem.