I think the cat stamp your talking about is a Magenta cat. Don't know who to buy from. You might also like the cats by
http://marysecarrier.com/page/eng/home.html I have been told she use to do images for magenta. She has a cool cat set with two heads of cats that I think would make a cute card.
I bought today at Michael's a set of stamps with a cat head, a bottle of milk, the word meow and a ball of yarn for a buck and I used my 40% coupon. So four stamps for 60 cents and a tiny ink pad. Haven't tried yet but they had a lot of cute sets. I tried not to look at them like baby etc. Was afraid if I looked I'd be buying more.