Thiel Owners

I'm looking for a pair of 3.5s as well as 1.5s.

@tomthiel

Hifishark (https://www.hifishark.com/) might be the "best" one-stop online source to check. They appear to be an amalgam of eBay, US Audio Mart, TMR, and other worldwide sources. You can filter results by country. Here are a couple of relevant hits:

https://www.usaudiomart.com/details/649548973-thiel-cs-15-pair/https://www.ebay.com/itm/143396134741

Beetle - thanks for the leads.
JA - I'm working on real quantities in the field. Thiel didn't compete well at its lower end. Dealers I knew thought those products made no market sense - they were too radically different from their price peers. In addition to quantities I'm looking into the 1.7 XO. A product announcement by Steve DeFuria (first sales manager of New Thiel, and old friend of mine) says they're 4th order Butterworth, and the Frequency Response Curve shows a 7.5dB fall from 100 to 20K Hz, a somewhat exaggerated Harmon Curve. I can't find reviews on the CS1.7 that show a bank of measurements. 

Upgrades for the 2.7s still down the road?

Probably several hundred pairs of CS1.6 out there but, I would guess, not many 1.7. I had an early pair of 1.6 (2002) and I think the serial number was in the 200s. I could ask the man I sold them to.