Severly,
I changed my rear bearings a while ago, and I think the Breva uses the same bearings as the orig. V7:
rear ; right is 6303-2RSH (47mm outer diameter, 17mm hub), left is 6203-2RSH (40mm diameter, 17mm hub).
You can check this by looking at the parts diagram for the Breva and the early V7, to see if it shows the same parts numbers.
Joe