Hi Craig,
An example of a 'Spotlight' shroud on a 12" truss Dob.
1.5m of red stretch cotton from Spotlight, 1.5m of black for the inside lining, plus some double sided Velcro from Bunnings for securing it. Total cost less than $20.
Just get the wife, girlfriend, or your mum, to make it up for you; whoever can use the sewing machine best!
Cheers

Chris