pig in a poke

31 Moby Thesaurus words for "pig in a poke":
      bargain, blind bargain, borderline case, chance, chance at odds,
      contingency, deal, dicker, double contingency, gamble,
      gambling chance, guess, hard bargain, horse trade,
      matter of chance, open question, piece of guesswork, potluck,
      potshot, question, random shot, sight-unseen transaction,
      sporting chance, swap, toss, toss-up, touch and go, trade,
      trade-in, undecided issue, wager