So, just for an out of the blue and completely random question, how much do you think that it would cost to have the foam carved by a rapid prototyper?
Forgot to mention; if you use the insulation foam, make sure you coat it with something like glue, or acrylic paint before you spraypaint it. There's a certain chemical in the spraypaint that will eat the foam away on contact.
Volume (cubic in.) x $20.50 + Height (inches) x $109.00 = Cost for the first Part
Volume (cubic in.) x $20.50 + Height (inches) x $25.00 = Additional Parts
which basically means that the chest and back plates would be roughly 3000 dollars.
Now, should you plan on going into large scale production of this armor, then yes, this would be worth it, since you could create the mold and then sell each armor suit and make back your money. Which that would be a fun job, now that I think about it