I’ve used these for helmets (Iron man, Black Panther, and Boba Fett) and they work great:
Wall Mounted Equestrian Helmet Rack https://www.amazon.com/dp/B008OB3Q9Y/ref=cm_sw_r_cp_api_fabt1_b9kXFbA7CVKTG?_encoding=UTF8&psc=1
They’re easy to install, sturdy, and pretty cheap. Depending on how protective/custom you want to get you could add some padding to it and could an art backdrop behind the helmet pretty easily if you prefer to have some flair behind the helmet. Haven’t found anything great to wall mount the gauntlet(s) so I currently just have them on top of a bookshelf but you might be able to find some floating shelving for them.
Wall Mounted Equestrian Helmet Rack https://www.amazon.com/dp/B008OB3Q9Y?ref=ppx_pop_mob_ap_share these work perfect
There are hangers especially for helmets, if you have a riding/equestrian store nearby they may be able to help.
Example from amazon: https://www.amazon.com/Wall-Mounted-Equestrian-Helmet-Rack/dp/B008OB3Q9Y.