Ever since Ben Cooper released its 1974 Evel Halloween costume (the mass-produced kind sold in a cardboard box with the plastic rubber-band mask and accompanying smock), countless trick-or-treaters, partygoers, and amateur daredevils have dressed up as Evel. Below are images stolen from all over the internet of store-bought and homemade samples as modeled by various lives of the party.
Note that as with many of the women's costumes, it's not enough to simply dress as Evel Knievel (or a cat or nurse or witch), but to dress as a sexy Evel Knievel (or a sexy cat or sexy nurse or sexy witch). Not that there's anything the matter with that. Also note the various identical store-bought costumes, as modeled by various folks. Personally, I prefer the homemade variety.
See more Evel costumes scattered throughout Knievel Rock (especially here) and Knievel Comedy. I myself appear in an Evel costume here, and more recently, here.