I have seen "rebuilt" rotors for the V-12 in several Lincoln parts catalogs, Boos-Herrel has them listed as part # 12201, '36-'48 @ $125.00, their phone number is: 215-965-8296. I'd check around, you might be able to find one for less.
If you have any of the Vintage NORS numbers I can look through my small collection of rotors and see. I am not too familure with the V-12 dist parts, so a pic or two may help also. There were a pair of NOS V-12 caps in the pile of stuff. Already sold them. Rod
Rowdy, they have 2 brass rings in the middle instead of 1 like a ford... and inbetween them is a raised disc to seperate them so the spark doesnt jump across
otherwise basically like a typical Ford 32-41 rotor