I found a 3.1" and holder!
I'm trying again. I have a 2.6" fine-annealed pyrex secondary in a research grade Novak holder that I would like to trade for a decent 3.1" secondary and holder (the holder should fit a spider designed for a 3/8" shaft).
I recently heard from the person who sold me this item. He said that the secondary gave great views, and was guarenteed by the compny he bought it from (D & G or Novak, he didn't remember) to be "better than 1/4 wave RMS". It has a couple of very minor sleeks in the coating, and a small (1 mm?) water spot.
I would be willing to sweeten the trade with cash or possibly an accessory you may need that I may have.
If someone would like to purchase this item, I'd be interested in that, too, if the offer is reasonable. If someone has a 3.1" secondary and holder they would like to sell outright, I'd like to hear about that, too.
The photo below is NOT of the item I'm offering. It is a picture I googled of a research grade Novak Holder. Mine looks identical, but has a mirror in it!