There are many helmets available if you want one, the one I choose after getting many recommendations from people on Facebook (Judge Dredd costume groups) is from Stephen Snowdon / Rabid Weasel Studios and comes highly recommended. It’s a fiberglass cast that will need some work.
The helmet cost 535:- + postage (£50, $66, €55) and is cast in fibreglass so it’s not a material that is tough to work with if you have an electronic multi-tool that let’s you do some cutting and sanding. I bought a pretty cheap multi-tool ($36/£27/€31) and it did the job without any problems. Most multi-tools includes the tools you’ll need when you work on the helmet but a Diamond Point Grinding set is something you’ll need to get into the smaller parts on the front of the helmet.
I had absolutely experience working on no anything like this but it was not as hard as you might think. All it takes is time, an electronic multi-tool, eye & mouth protection, courage and a steady set of hands. When you started working on it and see how the helmet transforms into a something you one day will wear with pride AND know that you made it ”patrol worthy”
I started cutting out a small piece on the front of the helmet to get used to using the multi-tool, it’s nothing that will take a lot of force from you when you work on the helmet (it’s more like cutting butter)