Here is the status of my quest for (new) P1800s or 122 disc rotors to do a PV drum to disk conversion:
1. Autozone - Special ordered Beck Arnley p/n 0830877/cross ref. to Duralast p/n 3499 front brake rotors for $60.99 each (supposedly solid); they came in, but were vented so they wouldn't work with the (new) 1800 3 piston calipers I have purchased.
2. Autozone - also Special ordered Beck Arnley p/n 0830190/Duralast p/n 3497 front brake rotors for $17.99 each (supposedly vented); they never came in and Autozone said they no longer carry them so they refunded my $.
3. Partsamerica.com (they are partnered with Checker)-- ordered Beck Arnley p/n 0830877 BRAKE DISCs online for $39.99 each. The next day I received an email saying they didn't have this p/n in stock, but would replace them with the "equivalent" Raybestos disc brakes, no charge. I received two boxes of p/n 9844/D17405 BRAKE ROTORs in the mail about a week later. The interesting thing was, although both boxes had the same part number/description on them, one box was a little bigger than the other. When I pulled the rotors out, they looked totally different--the stud hole spacings and hub hole diameters did not match one another--also, one disc was vented and the other wasn't. Neither fit either my PV444 hubs or the 1800 hubs (used) I received from Don Thimbolt. The solid disc rotor almost fit, except if you drew a circle connecting each lug hole, the diameter of this circle would just need to be about 1/8" bigger to make the holes line up with the hub holes. So close, but no cigar. (Also, the vented rotor wasn't even close as far as stud hole spacing, not to mention the disc was too thick for my calipers, again, being a vented rotor).
4. We ordered one last set of discs online..from (I can't remember where) and at the moment, I can't remember the p/n either. I think they were around $50 each...we'll get those in a few days and see if they work. I have to say this was a productive way to spend my vacation :P

5. For kicks, I looked up 1800 discs on the (new) Scandix site, and to my surprise, I see that they have pretty reasonable prices on disc rotors...(hmmm, competition is a good thing, afterall :))
Scandix description:
Brake rotor front all 122 and P1800 cars with one circuit brake system.
Single front brake rotor, this one is not ready to fit, it comes without the hub, you need your old hub and new studs to make it work, you might need to bring it down to the right size using a lathe, that work should be only made by specialists.
Required Qty in car: 2
Order number: 1001507
$ 75.00
13 items available

For this price, I could have saved myself all this trouble. Anyway, if #4 doesn't work, I'm going with the Scandix rotors. If they're out, Swedish Treasures has the next best price on rotors minus hubs (they also have pretty reasonably priced discs w/ hubs, if anyone is interested in those).

signing out.