Any particular type?
Reckon Kevin at Endicott's Surplus in Exeter would be able to sort you out for some Army wool blankets.
http://www.endicotts.co.uk/
Charity shops often have some, at least around here.
They may need dying though as some have "interesting" staining/marks........
Cheap, mind you !
Not sure on how they pack down but take a look at these.
http://www.britishmilitarysurplus.co.uk/ishop/1069/shopscr72.html
Not sure on how they pack down but take a look at these.
http://www.britishmilitarysurplus.co.uk/ishop/1069/shopscr72.html
Nice and cheap doesn't say what size they are.
I'm not even gonna click that link, as I'm sure the blankets are priced in organs! How many do you get for a spleen?