Oooops! Well, I guess I will suggest putting this on your wish list!
Kitchen stores have them, office supply stores have them and I got mine from RBI: http://www.reptilebasics.com/My-Weig...l-p-16191.html
It's great to have one of these so you can track their weight and weigh their food when needed.
What size prey are you feeding now and are they mice or rats? Did you get the snakes as babies? Do you know about how old they are? Maybe a picture with something else in the frame as a size reference would be helpful