Hi Richard - Maybe you have figured out this isn't the most active forum on the Web. I just take a quick look every so often myself. Anyway, I saw your post finally.
I think everyone would love to see pictures of your Cirkuts, if you have a way of posting some. As to selling any, probably eBay would be the thing to consider. The market for Cirkuts has really died out with the difficulty of finding film, and digital/stitching taking over. If you aren't in a hurry to sell, you may want to start searching "Cirkut" on eBay, and get some idea of prices. However, #10s are few and far between, so it may take awhile to see one sell.
The original lens for a #16 Cirkut was a Turner-Reich 15"-24"-36" triple convertible. Look on the bed of your camera and see what is marked on the focusing scales. I'm guessing you will find 3 scales, marked for those 3 focal lengths. Over the years T-Rs came in a variety of shutters. I don't know which shutter would be "correct" for your camera. These lenses do show up on eBay from time to time. However they are supposed to be able to cover some of the larger formats like 11X14, so those users bid on them. I believe sometimes (maybe not always) this lens is marked "11X14" on the front ring surrounding the glass. Ones marked "8X10" are a 12" FL and not what you need.
I've long dreamed of having a #16, but I've seen enough posts by people who have used them to know shooting with one is beyond my talents. I have no idea what film would cost, if Ilford or someone would even cut rolls to this size, but I'm sure it is many dollars per foot. Do you have the tripod gearhead for the #16?