Amazon - Prime $12.50, but another vendor has them for $10 + $1.85 shipping on first pack and +.60 shipping on each multiple pack. I bought 3 for $33.05 including shipping, no tax.
Anytime I can get them < $1 per card, I feel like I'm doing well. This came out to $.73 per card. I use a card per cage so go through a lot.
I bought sticky traps from this vendor before without problems.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1