Check out partsconnexion 'special' pricing on CAST varients, which has been going on for the past few months.
2.2uF / 630VDC, CAST-PIO-Cu, Copper Foil, 66mm D x 62mm H
Special pcX Price: $289.95 USD, Each!
$776.00 $289.95 pcX USD
vs
2.2uf / 400 VDC, VSF, Copper Foil, 39mmT x 55mmW x 45mmL, Each
$355.85 $302.48 pcX USD Price