You could always try and make your own body form...
I've seen people make bodies out of duct tape and stuffed it with paper and stuff.
Check out this link:
Halloween prop using roofing tar
You could make a wooden frame and make separate body parts and put them on it.
I'm doing a really bad job at explaining it... But it's possible!
I plan on doing it for my haunt this year.
Hope this was of some help... lol!

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