I bought a quart of oil based black paint from the "Tractor Supply" store, (in case you have one near by, It's just a hardware store chain). I thought that oil based paint would stand up better to getting wet frequently. It was very easy to apply. I painted it on pretty thick and did 2 coats +. After you apply a coat, whatever paint you choose, shine a light from behind it and then look through the front. Doing so will reveal any missed spots or streaks where the paint isn't thick enough, so you can do a few touch-ups to make it perfect.
The paint I used was "Majic Tractor, Truck & Implement" Exterior Oil Base Enamel - 8-2959 Matte Black", and is manufactured by Yenkin-Majestic.
It looks Matte, but also you have the glass in front of it that doesn't exactly make it glossy, but rather "glassy", if that makes any sense. Check my profile where I have a couple photos up.
Hope this helps,