Here's a bit of info from the Wilton forum. http://www.wilton.com/forums/messageview.cfm?catid=8&threadid=124308&STARTPAGE=1&FTVAR_MSGDBTABLE=
Where to order, I have not a clue. Tried Squires without any luck. Amazon?
The shortening equivalent in the UK is Trex, or Cookeen. You get it in the butter/margarine section of the supermarket. It's called Vegetable Fat instead of shortening. Just make sure you don't buy lard, cos that's animal fat...
As for whether there is a hi-ratio equivalent, I don't know. I think that shortening/vegetable fat has a larger following in the US, so in the UK there is less choice.
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