Welcome Philippe.
Yes, that can certainly be an issue with older disc players. Perhaps it would be best to contact McIntosh US directly. The MS750 isn't really that old (2007), so I'd be surprised if spare parts are not available, though it was made at a time when DVD drives were on their way out and BluRay and HDDVD drives were coming in. Even then, Sony certainly made thousands or millions of that drive. This is speculation, but it could be that the distributor is uninterested in helping you find parts and fix the unit versus sell you a new unit...which is a shame. It may just require him to find the model number of the drive unit, then contact McIntosh US or even Sony.
