Yet another noob looking for help

Whats up people.

Some months back after completing my Stormtrooper bucket i picked up on of the Rubies two piece jango helmets with the intention of improving it (as its only my second helmet and if i'm going to cock up, better to do it on something cheap). Nearly a year later i've finally got the time to go ahead with my plans.

What are the plans you ask?

well thus.

the two parts will be glued and filled with the good old tape on the outside method, and i'm hoping to buy a t visor rf and stalk from bobamaker to help it on its way.

But i was hoping to strengthen the overall helmet and heres where i need help. My intention is to apply a few coats of resin to the inside, this will hopfully thicken up the helmet and add some weight, after that has been done i am planning on adding a coat or two of fibreglass to give even more strength, this will also wrap around the bottom rim sealing in the resin where it will be sanded to shape.

No i have the feeling i'm going to sound really dumb here, but having never used it before, whats the type of resin i'll need, and where can i get it in the uk. i'm after the stuff that some buckets are cast from wholly, any help would be great.

i'll hopefully have some progress pics the weekend after thisone coming as its payday and i can get some materials.
i'll be sure to post up some pics as i go.

quick question, does anyone know where i can buy polyeurothane (probably mispelt) resin in the uk, its a cruicial part of my plan.

also whats the actual thickness of jangos helm. at the moment the rubies is about 1.5-2mm wide.