I can understand the attraction, but I don't know why either!
I've had two, an early 1965 version in the early 70's (the one with the casing around the carburettor and the rounded engine casings) and a 1977 "Oilmaster" (who came up with that model name!) in the late 70's.
They were strange but enjoyable - the first got the high bars/backrest treatment, which I thought looked quite good with the long standard forks, and the second got wider bars - sort of Californian thing.......Now that I think of it I had a CZ 175 with my brother as well, stripped down as a scrambler.
Cheap fun at the time, and probably still - as you say new bikes still avaialbe for about £3000!
I have some photos somewhere....