my trusty old purple GT mtb, still shiny, has shark worn sprocket teeth
and despite being bought at my LBS, the LBS mechanic says he has seen other GT bikes in the area but never the particular hub/cluster that is on my bike (519 rims)

I've not seen how it mounts so I dunno but any suggestions on should i get the same cluster despite or is a new hub and respoke the old rim to it is not really that difficult to do ?

or just buy a new wheel ready to go ?

also, i'd like a better first gear (Bedford Creek) or convert it to a 9 speed ?