They aren't 8,000 to 1. They were +8000 a couple places about a week ago. Best I can find at the moment is +5,000. But those numbers are the return on a $100 bet, not a $1 bet. Odds of +8000 means that the odds are 80 to 1.
Your $10 bet at +8000 would win $800, not $80,000. I don't bet on the Blues anymore out of superstition, but if you can still get them at +8000 that's probably the best their odds will ever get this year.
I'd be betting several hundred bucks on the Blues to win the Cup if the odds were 8,000 to 1. A $125 bet would be a $1M payout at those odds.