My Dragon was made from a foam sheet that they use as mats for stables
It is very light and cuts easily with a very sharp knife but resists tearing well (very much like camping mats) costs about £25 for a 6ft x 4ft sheet but only found it at a feed supplier/tack shop
One thing to be aware of is it is a very good insulator and you will sweat well under it (I end up soaked after an hour in the dragon and that is at night)
Just an off the wall idea that would work for a one night type suit
Have you seen that stuff (think it's called bind weed) that sticks to your clothes and grows wild in run down gardens and wasteland (kids call it sticky plant or something )
If you could find enough of it it would turn you green and planty
and it sticks to anything
Other thought is those cheap tarpaulins that come from machine mart or the like
They do a camo one
Failing all that a cheap camo boiler suit (paintball type) with a quick trip to the ex-army shop for some leaf netting
Jason