Clay - $100
Silicon - $160
Shell - $60
Gallon of resin (3 or 4 helmets worth) - $90
Foam Head - $10
Turn Table - $10
Blue Visor - $30
Pipe and Flange - $10
Make yourself a budget of $500 if you're planning on doing it - Just to let you know. But once you have one, you can probably make helmets for $50 a piece (visor being the expensive part)