The lady from tweedsidejacobs.co.uk may have some for sale, not sure if hers are registered. I think she was on TAS, or you can check her website. They are in St Boswells.
I bought some (non-registered) females from Nicki at edengotlands.co.uk a few years ago and they are lovely sheep. She's in Cumbria, near Penrith.
Shame about their feet though, and their fleece this summer was completely felted on the ewes
The Shetland crosses are really nice!