Sorry bud - this is not a "I want this in under a month for Halloween!" type hobby. Sizing, pepkaura, fiberglassing, bondoing, sanding, painting, padding and strapping a full suit of armor plus getting additional supplies like an undersuit, gloves, and balaclava all shipped to you before Halloween is just not going to happen in time - especially if you're just now getting interested. The days are about to rapidly turn too cold for resin to properly activate in time.
HOWEVER, don't let this discourage you from making a set of your own armor. There are other ways to approach this such and make it in time for Halloween. A current popular method is using basement flooring foam or EVA foam which can be be easily cut and can be formed with a heatgun/hairdryer . This just requires you looking at photos of the armor pieces and working by eye to make the suit. There are no blueprints or anything for this type of armor making - you just need a good eye and talent - something that you're going to need regardless of any path you take to make one of these suits. The foam is relatively inexpensive and comfortable to wear.
Cheers,
Kensai