I know nothing about their variable speed drive but... Their 15inch drillpress used two custom bearings on the driven pulley. Normal outer race, marked normal number on that race. The inner race was the normal bore but it extended out from one side about 2-3CM beyound flush. That bearing is not really available. Rumor is NTN made something to fit. I was able to fit larger inner bore bearing in with an inner extended stepped sleeve.
Their 20inch drill press is all normal size bearings.