You can change the size of the image really easy with paint.net.
The text will probably be unreadable because the image is too big anyway. I'm unfortunate to say but you'll probably have to make one yourself as I'm not good with designs. A player from my own hotel made one for me.
Badges above the head has to be 30x30 or 35x35.
30x30 It is I believe. I've tried it with my staff badge as well, but had to get another custom one that would fit, because my 50x50 badge wasn't centered either.