Hmmmm naky huh
Well here are a few. I dont know what the sig looks like but it would be cool if you had the guy faded into the background, but if it doesnt look good do whatever you feel is best. ^^
(this is the most complicated, and if you use it could you make his hair white.)
http://i5.photobucket.com/albums/y18.../Aquaman02.jpg
(My avatar could work very well)
http://www.lcomics.com/IMAGES/pic/nav/right_aquaman.gif
(this is my least favorite, most likely beacuse it wouldnt look well in the background)
http://stuff.thathappened.com/albums...or/Aquaman.jpg
I actually have a really cool picture like the last one but its way better. Unfortunatly its in a book! I looked for it on the web but couldnt find it

Oh well.

Good luck!