Is there a way, short of using WP custom menu, to have an image in the pages menu?

indonesiaetc.com
WP 4.1
Atahualpa 3.7.15

Happy New Year!

I have the regular Atahualpa "pages" menu in my header. I am using this because the WP custom menu was misbehaving and disappearing from time to time and I could not figure out why. Besides, it's not a particularly complicated site and I don't really need a mixture of link types in my menu.

BUT I should like to have one of the links to a page be an image. At the moment the farthest right-most link is to the "Donate" page. It looks like all the other page links. I should like to have that be an image (specifically, the PayPal "Donate" lozenge similar to this one https://www.dokuwiki.org/lib/exe/fet...ter%2Flogo.jpg)

I suppose I should be looking for a way to do it with custom CSS inserts. But nothing is coming easily to mind.

Any quick ideas? A search of the forums did not yield any obvious solutions.

Regards