Hi,
I have a double decker hutch with an apex roof and I rang scratch and newton who will make one to your dimensions, but they are expensive.
I wanted one really to stop the rain, as my bunnies come in during the winter, and I got a clear tarpaulin, which is was loads cheaper and does an excellent job of stoping the rain going in the hutch and the run, but obviously wont keep them warm in winter.
If you want any information on the tarpaulin company give me a shout.
Carole