Bushwalk Australia

I have a couple of old army rain jackets from the Vietnam Era that I am trying to conserve and rewaterproof.
What I need are some of the extra long ballons that I can insert into the sleeves of the coats [ inside LDPE bags] so I can do a coat with some diluted silicone. My Google-Fu isn't working. Any body know where I can buy a dozen> arm sized ??

Just get any balloons, if you can't get the sausage type ones-put them inside the sleeve-then inflate and keep chucking them in. Worked for me.

Thanx Lamont
If I can't get any long balloons I will have to do that. Then the next problem will be getting the silver colour of the inside coating correct, most silver or aluminium paints are not at all flexible