Have you tried making a duct tape dress form? Even with the store bought ones they will not be an exact duplicate of your shape and it will need adjustments once delivered.
If you haven't tried to make a dress form it might be worth it to try first. Here's some Craftster's posts on making the dress form:http://www.craftster.org/forum/index.php?topic=346512.0http://www.craftster.org/forum/index.php?topic=341386.0
I'm not sure what tape options are available in Trinidad. You will want something heavy duty. The duct tape we have in the states have little strings in between the tape layers running both vertically and horizontally.