What hand that villan shoves with are you ahead of here? Other than a straight bluff with air. Even on a bluff villan has at least 2 cards higher than a meaning you will not be a big favorite even over a bluff. You are dominated by any pair 6 or higher and any A-7 or higher and only a slight fav over a hand like KQ. Ace small is a hand too many people don't know how to fold. I will play A-X suited if there are multiple players in an unraised pot but not for most of my tournament chips.
Let him take your 50 chips and move on. Maybe he will try it again when you have as real hand.
Which I did, he proceeded to do this 5 more times after posting his blinds, so on either my small or big blind, Called him with pocket jacks and he showed 64 off. That i'll teach ya.