You need to buy a new sticker. The stickers are for each machine, not each person. Otherwise, you'd stick it on your helmet for the season, instead of the sled.
Having the receipt that you purchased a sticker already means absolutely nothing. If you had peeled it off and sent that 'void' sticker with the receipt, you may have been able to get a $5 replacement sticker. Not sure. They have to do some checking there or you could just rip off other people's stickers and bring it in for a new one for $5.
I had both mine and my husband's stickers in my pocket last weekend as it was -15 when we woke up to ride for the day and I didn't think it would stick. We were stopped and had to attach them right there. Technically, we still could have been ticketed (and he told me it's actually a misdemeanor) but the officers (Marquette county Sheriff's, not DNR) were super cool. They understood it was cold, they helped rub them on good so they wouldn't come off. His exact words- how do I know you don't have 6 snowmobiles at home, and just want to ride around with one in your pocket all season?
If you sell a sled mid-season, you have to buy a new sticker to go with your new machine. The guy who bought your old sled got a free pass this year. Something to consider when selling, I suppose you could ask the buyer for an additional $35 to cover the sticker.