I was going to get these:
http://www.mouser.com/ProductDetail/Nichicon/PCX1C470MCL1GS/?qs=sGAEpiMZZMtZ1n0r9vR22UdLYVQX4pPxWiS5P1Zoi%252bM%3d
But according to your suggestion, these would be better:
http://www.mouser.com/ProductDetail/Nichicon/F911C476MNC/?qs=gmcn8Ik9O3ES451T9B7NoQ%3d%3d
I've always been under the assumption the metal cans like these don't leak. *shrug*