I've always had a soft spot in my heart for Marantz because they made my first stereo system which I bought as a teenager in the 70's.
After the listed equipment was made, yes, Saul Marantz sold the company to SuperScope, but they actually expanded their lines and made some really great looking stuff that sounded good and was within the reach of normal people. It was also very well made.
That said and admitting that these pieces will still sound good, they will not sound great.
Case in point: around 25 years ago, Audio magazine (R.I.P.) reviewed Marantz's totally authentic, limited edition recreations of their two legendary solid state offerings from the days when Saul owned the company. It was a pre and its accompanying amplifier.
Marantz (by then half of D&M Holdings with Denon) spared no expense to make as faithful a re-issue as possible with only a few updates and improvements to the cases as well as replacing unavailable parts with new ones that were actually better than the originals.
After an exhaustive review that spanned around 8 pages of the magazine and included a full cadre of bench tests, the conclusion was: this stuff is a bit of a disappointment. Not bad, but not great either.
This was both from the reviewer who listened and the tester.
The equipment had garnered such a legendary status in the ensuing decades that it couldn't live up to the hype. It may have been transcendent in its day, but that day was gone.
I understand gear lust (have had it myself), but this equipment can no longer be considered high fidelity.
Also, even lovingly restored, these pieces are going to offer very little bang for the buck. I imagine that they aren't going for $600 each.