ITAC Mouse-Trak bearings

[Pompom58]

Hello guys,

I have an ITAC Professional Mouse-Trak and I would like to change the bearings as I have a clicking noise in one direction which I would like to eliminate (and I don't see where else it could have come from).

Would anyone with this device be able to identify the bearing reference? They are NMB bearings on my unit and I bought L-940ZZs but they don't quite match in terms of internal diameter and I can't find the right part number (no response from ITAC, to whom I sent a message).

Thanks!

Edit: problem solved