I have a 74 Ramirez cedar top w/ Brazilian rosewood that is a decent example. I value it around $3500.00- $4500.00 USD.
The problem you will find is that these are 664 scale guitars and the market is going to 640 or 650 guitars.
I have taken quite a few commissions for 640 and under guitars but never for anything above 650.
Also, they don't come with any relief in the neck with many having very high action. Richard Brune does a fretboard retrofit that makes these guitars play very well but it is a bit pricey.
Now the sound, IMO a Cervantes concert Rodriguez sounds,plays and is an overall better guitar than my Ramirez. And the master series Cervantes is miles better in sound, playability and construction.
By the time mine was being made (74) they were starting to really apply the heavy polyurethane finish. But they do have the Ramirez name which for some reason carries lots of weight with many people still.