I used to have a Wivamac DB1000 and replaced the bearings on it twice. It wasn't too difficult to do.
Depending how old yours is, you may have two front bearings. Mine had and I was advised to get the bearing cap modified to use a single bearing as the double bearings which were originally intended to reduce play actually caused faster wear. I got mine modified and fitted a single front bearing.
The order of removal is - rear bearing first - loosen the grub screws and then remove the bolts and bearing carrier then file down any burrs left by the grub screws (so they don't stop the pulley sliding off). Then loosen the spindle pulley and then remove the bolts from the front bearing cap and withdraw the spindle from the front of the headstock, sliding off the pulley as you do. Once the spindle and front bearing cap is removed, you can separate them by removing the circlip from inside the bearing cap.
I think the trickiest part was getting the pulley to slide off the spindle because of the burr left by the grub screw.
Before you do all this, get a new drive belt and replace that at the same time.
From memory, the front bearing is a pretty standard sealed bearing. The rear bearing is a spherical bearing and that may be a little more expensive. No doubt Wivamac can supply them if you can't find them locally or online.
The interesting bit when you reassemble is getting the spindle aligned along the axis of the tailstock quill. this isn't straightforward and is probably the biggest shortcoming of the DB range.