Here's an example of the two types of vinyl stickers that have been produced in 2007 for the Eagles' 25th anniversary, to give you an idea of size.
They're vinyl stickers printed on a white background and should hopefully last a while, despite being 'affordable'.
I've had one of each on my scoots and they made it to the Ace Cafe, France and Germany without falling off or fading - so far!
First is the the red 25th anniversary Eagle (A better version can be seen on the website's message board page).
The red anniversary eagle is square sized 11x12cm and works out at 45p per sticker.