9/32 it was, 7.14mm, chrome balls ordered. Thrust bearings 1/4 and bracelet ones 3/16. Thanks for your comments.
BTW I think 1/4″ rollers are too big for the thrust lever so I shall experiment with smaller dia ones to get over the shoulder and nicely into the taper, per the article in “Technicalities”.
What a genius he was.
