How "Rare" are Audio Classics, Really

Sellers often say things like "RARE Eucalyptus finish!'" or increasingly RARE and hard to find!

I like to read about cars, where if a certain Porsche or Ferrari numbered only in the hundreds they are indeed more valuable than mass produced models.

Collector cars which number in the single digits can cost more than a nice house in Santa Barbara.

Which makes me wonder: how rare, really, are certain collectible audio components, in terms of their production numbers?

How many Tympani IVa's, Audio Research D70's, Marantz Tuners, McIntosh power amps, Rogers LS35a's etc etc have really been made?

Please note this question applies only to real classics, from reputable manufacturers.

Your purple gull wing doored fiberglass kit car replica of Magnum PIs Ferrari may indeed be "one of kind", just like your garage built electomagnetic shielding devices and custom African hardwood enclosed power stations, but a no reserve auction will quickly confirm the true value of those "rare" items.

What are the most rare, classic audio components, and how many might remain in the world today?