The Invincible Iron Man #84 (1976)

 "The Night of the Walking Bomb!" Story by Len Wein. Art by Herbe Trimpe and Marie Severin. Tony Stark's friend and erstwhile Iron Man stand-in, Happy, has collapsed from injuries sustained while wearing the Iron Man armor. Can Tony find a way to help his friend before it's too late, or will Happy become just another casualty in the pursuit of justice?

Note: the Marvel Value Stamp was removed. Fair condition.