The laser needs to focus on two specific lengths, one for CDs, the other, infinitesimally different: SACD layer. They get old/weak, and out of alignment, quite difficult to re-align a new one if you can find it.
I suggest: find your model on eBay, a lightly used one (not many hours on the laser)
a. your exact model, keep yours for parts.
b. similar Marantz model
c. YES, get thee a Sony xa5400ES player. It is awesome, here’s my story:
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