We at Robopromo have iron-on vinyl numbers available. Also new this year you can have numbers custom cut by us to complement your robots style. If you haven't bought that kit yet, you can buy one from us and we'll even iron the numbers on for you. Here's a link for the numbers on our website:
standard:
http://www.robopromo.com/product_p/rp-2006.htm
custom:
http://www.robopromo.com/product_p/rp-2014.htm