fdd5d689_e_Notes_on_Coupling_Capacitors__Impressions_HV
[Brand] DIY HiFi Supply Obbligato - Metalized Polypropylene in Oil, 4.7uF, 630V (w/ radial leads) $6.75 [Impressions LV] . [Rating] 3½ [Impressions HV] 
DIY HiFi Supply has these custom made in a variety of sizes, some large enough for power supply use. They stress that they are very tightly wound without any voids. There is also a premium (axial leaded) version, but being cheap I have not tried them. Overall, these caps are quite good, and considering the price, very good. Maybe not quite as resolving or as euphonic as the Auricaps, these caps are just very neutral with no appreciable flaws. Bass is solid if maybe a little sluggish, treble is clear without any hash, and midrange is where it should be. Really, for the money, I doubt you can find a better cap. The only real downsides I see is that shipping can be a bit slow as they come from Hong Kong, and because they need capacitor clamps and are 40mm in diameter (I can't find 40mm clamps anywhere), they can be tricky to mount. Get some of these, you won't be dissapointed.
ecp audio diy: Some Notes on Coupling Capacitors
Impressions HV