Hello , Graham. Welcome to the Family and hope you enjoy it enough to call it home for all your BBQ needs.
I have no Copycat recipe , however, with a few trial runs with a homemade Rub could give you a very good personnel recipe to share with others.
I have found that, with Ribs ,one can add Turbinato Sugar(Raw), to a Spice Rub , can add a whole new level of taste to your Ribs.
Here's a starting point:
(amounts are up to your taste)
Paprika(smoked if possible, about 3 to1 to each of the other Spices
a Pure chile powder- one that is not mixed with anything else-like Ancho , New Mexican or Anahiem . A commercial Chili Powder will do ,But cut back on the Salt , not as good , but will do...
Cumin
Sea Salt
Oregano ( rubbed to powder)
Onion powder
Garlic powder
Trubinato Sugar - or - Brown Sugar if the Raw Sugar isn't found. 'note: Br. and white sugars burn quickly and must be watched. Turbinato will withstand the heat much better .
Have fun and develope you own flavor, most anything goes...
Here's a shot of my Ribs:
I do not wrap them in foil and they come out great...