There was this strange 1976 Enco Toys Spock Star Trek Space Fun Helmet. Read more about it here.
But plastering SPOCK on the helmet as on the box was optional; it came with a sheet of decal letters, and so the kid who got it could choose which character’s name to put on the helmet. I tend to imagine the non-Spock ones are more collectible. Which brings us to STAR TREK SPACE FUN HELMET JANICE RAND (With FLASHING LIGHT EMITTER, but I left off the PULSING SONIC SOUND)!