I just went through this exercise with a W&W case. I don't know how similar they are, but FYI:
- 1st step was to pull back the lining. The axles were held by a plastic insert, which was screwed to the rest of the case. Some of the screws were covered by tape which made them less obvious. Undo the screws.
- The axles were 8mm riveted on the inside end. Hold the outside end of the axle somehow (I used a vice) and a large diameter drill to remove riveted part.
- Measure wheel diameter, axle length and diameter, wheel thickness at the hub.
- I found in-line skate wheels where the best match. You can buy generic luggage wheels, but they all had 6mm axles, whereas the original where 8mm axles. The inline skate wheels were slightly narrower at the hub, so that affected the required axle length.
- You can get axles with screw in ends (instead of riveted) from Ali Express. You can also get standard in-line skate axles, but they will probably be too short. You will need wheels, bearings, spacers and axles.
- Assembly is straight forward
An alternative, in principle, is to just replace the bearings. They all seem to be 608 bearings, but I couldn't figure out any way to get the old bearings out of the old wheels, the old wheels were pretty worn and the inner race looks like it is "extended" so there was no need to for a spacer. Buying bearings with an extended inner race, or fabricating special spacers seemed harder and less satisfactory than just replacing the wheels.
Oh, and one other thing to think about: My wheel replacement went well, but now the handle is broken! I'm fabricating a new handle, but I'm thinking maybe I should have just bought a new case.
Photos