Not that regular screw-on freewheels are particularly cheap, have you thought about the XC Pro rear hub that takes a screw-on freewheel? The set I used must have been made by Suntour just before the ones pictured in your thread - same decals, grease injection ports, sealed bearings....just threaded to take a freewheel.
It's microdrive and will only fit the microdrive cassette.
It looks like there is a flash of silver just past the end of the threading.. so 7speed.
But a picture from the axle end would confirm either way.
They are nice hubs and nice cassettes to put on.
Getting them off after a few years is another matter
Depends what you are willing to pay, hubs shouldn't be too much cassettes not a lot either normally.
May take some time to search, ebay seems expensive for the hubs at the moment.