Okay, this is months late and if you wanted it for Saturnalia festivals it is way late. That said...
Check out this site
http://legvi.tripod.com/armamentarium/id116.html
I got one of these. It's an inexpensive red blanket that works fine. Very easy to beat up and wear too. Stand out in the rain for a while, be sure to let the hem drag in the mud as you walk sentry duty. Then sleep in it. It will pass.
Bona Fortuna.
Ericius.