Much upgraded PM-80 with copper-plated chassis, OFC-wiring, transformer (toroidal), caps (custom-ordered to ELNA), knobs (solid aluminium) and added top plate (3mm aluminium).
Bar the absence of tone controls, the circuit itself is exactly equivalent to the original PM-80 so no 4-gang attenuator and no Mos-Fet output transitors - see the PM-80 page for the details.
Better is PM-88aSE (SE version of the PM-88a), PM-90 or PM-99SE.
Now, don't ask why the upgraded version of the 80 wasn't simply named 80SE - that's because there is a market-specific export-only but slightly pared-down version of the PM-88SE named PM-80SE which seems to mainly have been a 88SE sans copper-plating (and black only).
Sometimes Marantz really works like Luxman :)