Max - it could be slightly more affordable to make your own armor - check out leg xx's site:
http://www.larp.com/legioxx
A helmet is difficult to make and expensive to have custom made. You'll need to check vendors like LaWren's Nest, Find-It-Armory and Soul of the Warrior (for US vendors anyway). Make sure you contact those vendors to make sure the particular helmet you're looking to get is In Stock before you order! And don't be afraid to look around for a helmet in stock.
I'd suggest you save up your money and buy a good helmet made, rather than trying to make your own. IMHO you don't *need* to have armor right away to play as a Roman...And at that, I'd also suggest you have a good tunic, helmet, Caligae boots, gladius, and a Balteus belt made before you dive into armor.
Just realize too, you will likely be paying $200+ for both a helmet and for armor (new), sellers [on ebay for instance] offering an armor for $60 should be very suspicious. But, also take notes on the Leg XX site, and if someone happens to be selling a used armor for 'cheap', you might just get lucky. Some of the "cheapo" armors are convertable, so if you do happen to get stuck with a cheap lemon, you could still salvage it if you don't mind putting work into it.
Also on Leg XX's site is a listing of area Legion groups - check that and see if you're near any of the California groups, like Leg VI (L.A.) and IX Hispana (San Diego and other areas) ~ both are great guys and willing to help!
good luck!
Quote:Did an elephant sit on your pilum?
Nope, apparently it was *thrown* at an Elephant!
hock: