I wasn't particular, just put shimano 8 speed into my browser for Amazon; see one (US) for $16 --- HG 31, but think mine was HG 40. Just a steel cassette. I'd show the lack of wear, but ES won't take my photos and I'm not going to bother trying to reduce them.
I'm trying something different for an experiment since I use very few gears with my BBS02 and trying for a "perfect" chain line. Spaced my cassette out to a three
speed with eight speed spacing 11,17,28 and it seems to work perfectly (shifting at least). Also changed to 30 chainring; cuts speed to 24 mph or so, but want to see
how it ascends gnarly crags off road.