We have alphabet stickers Kathryn but probably nothing that is quite big enough, you prob wouldn't be able to read them from sitting behind. The other problem is the weather i.e. if you stick them on the outside of the window they probably wouldn't stay there long. My brother does stickers has a computerised machine. If you pm me what it is sposed to say and how big you want the total sticker to be I could ask him about it and how much it would be. The stickers he makes are for outdoor stuff and perfect for what you want. He does it as an on the side thing as well as through his work. I'll hit him for a good deal for you and then you could pay the postage if it works out an ok price.

Cheers michelle