Can't remember the make of mine, but must admit, although design has never changed mines about 15 years old anyhow, and they likely don't make the exact one now. The only thing I'd say, is alway buy an extending one, never the 'fixed' smaller (cheaper) ones, and alway examine the knee pad, cause some of the new ones are pretty tough, and aint that comfy to use (+ you dont get as much stretch when it's a tough pad)
Ignore the silly (in my opinion) hand operated thing that was around a few years ago, they're too slow, and only realy for fitters that can't kick a normal one !
My stretcher is battered and the knee pad has a great big cut through it, but believe me, it's far comfier than the new one I bought for £85
If you want my advice, buy one off ebay, just make sure :-
a) There are no (or few) missing spikes
b) The extending mech is working
c) no other damage
d) Older is likely better providing above Q's check out
Good Luck
(any more advice, just ask !