First you have to buy the proper historically accurate gear depending on your chosen gladiator type, replica gear of course. If you were to purchase real antique roman gladiator armor and/or helmet(s) it would cost you in the tens of thousands (US dollar) easily. Also antiques are not sturdy!
Replicas are the way to go!
It is very easy to find typical brass or light steel gladiator helmets online for under $400. Most of them are in the $200 to $300 range. However, you get what you pay for. Those helmets are all mediocre and fit too tightly on the head. They are also not historically accurate. They are too small. The brass is total junk. (in my opinion) If you want authenticity, commission a professional armorer to make something for you. That's the way to go. Bronze is a good metal for a helmet and is what the real Romans used. I am sure you have heard of the famous bronze age. But bronze is heavy... very heavy and is not reasonable for those who choose to re-enact the epic ancient spectacles.
Here are a number of grand quality armorers who are great to commission if you are very enthusiastic and legitimate about getting roman gladiator replica armor.
#1 hands down: The Ancient Sculpture Gallery. They are professionals of grand proportions concerning ancient art reproductions, and if you are willing to pay anywhere from around $799 to 5K for an ancient helmet that is very finely crafted. (I am sure there are probably different price ranges though depending from project to project) there is your place. They make the Ferrari Enzos and Bugatti Veyrons of the armor replica world. Quality, quality, quality!
Nix Imperial also has some fine work
Same with a number of other places including Valentine armories etc.
Romegiftshop does good leather work. (gladiator arm guard replicas, and kidney belts etc.) Good brass ornaments too. They are very nice people too.
There is no such thing as a real modern day roman gladiator and you can not become one. It is not allowed in modern society for it is dangerous amoral and people will get hurt. However, re-enactment events are fairly common. They are a fun thing to get into if you love history and are fond of Roman history in general... or are a zealot of Roman history. In these events, they use wooden weapons and/or dull metal weapons depending on the society.
There is no Larping in the legit re-enactment world, but Larp swords, shields etc are good if you just want to have some fun w/ your friends w/ your gladiator battles. Larp weapons are made of sturdy foam in case you aren't aware. They are very safe and cool looking.
Good societies for reenactment: SCA (society of creative anachronisms) (Within USA. They do mostly knight stuff but they do have a roman section of their society.)
Collegium Gladiatorium is good if you live in Europe. I thinks its mostly Italy... They might have a branch in (UK) though.
List of a number of the more common gladiator types:
Murmillo
Thraex
Secutor
Retarius
Hoplomachus
Provacator
Samnite and Thracian are the earlier versions of the Murmillo and Thraex.
I hope you found this information to be useful
How old Do you have to Be To Be A Roman Gladiator ???
What kind of armor did you use/Do you want to kill me?/how did you become a gladiator
a gladiator
Gladiator helmets had a grilled front, and a visor, Although the type of helmet and even whether or not the Gladiator would wear one depended on the Gladiator type.
It is called a lunista
How old Do you have to Be To Be A Roman Gladiator ???
What kind of armor did you use/Do you want to kill me?/how did you become a gladiator
How old Do you have to Be To Be A Roman Gladiator ???
The site of gladiator fights was the Roman Colosseum
Gladiator.
a gladiator
Spartacus.
retiarius
For entertainment.
Gladiator helmets had a grilled front, and a visor, Although the type of helmet and even whether or not the Gladiator would wear one depended on the Gladiator type.
Why did you fight as a gladiator
a roman gladiator, who goes by the name of odlid