Slightly off topic, but I saw a darling Studio G clear acrylic set at Michaels the other day that had a cute "Bella" style prego lady and the words "she's expecting!" and then little stamps to use on an invitation(what,where, when, rsvp, etc). It was in the dollar round bin by the Martha Stewart display in the Michaels I shoppped in Nampa, ID. Maybe this would work for you if you aren't able to find the stamps you're thinking of!