I’d guess something with a 10mm ID. The ones in it are 12mm, and too big. If 8mm is too small to fit the axles, then the axles are probably 10mm by process of elimination.
In that case, you want 16100-2rs bearings.
Dunno about the rubber washer, but the spacer goes between the bearings (inside the wheel), and the speed ring usually goes on the axle between the hanger and the innermost bearing.