For tags, there should be plenty available, just make sure to get your buck tag the same time as your doe tag. If you purchase a doe tag after the season starts you can no longer purchase a buck tag.
Does Vermont have a replacement website for Hunter Safety Course? They should have some way to track down your number. I was born before 1980 and lost my card but still decided to have it updated on the Illinois website for hunter safety cards. I've never been checked for a hunter safety card in the field before but then again, I was born before the 1980 mark.