Dan,
Sandhill has Al McGraws line of Manx Rumpies and have seen some silver spangles that came from there. I have a pair that are rumpless and am trying to breed them as Araucanas. I can not post any pictures unfortunately since I don't know how to do such.
Al's son was selling chicks of the birds you are speaking of and maybe you can contact him for some new stock.
by Dr. Albert McGraw
424 County Road 93, Box 132
Anderson, AL 35610
Here is the last address which his son was living there when I talked to him on the phone. You will need to do a search for the phone number but his son I believe has the same first name. Good luck.