A Minolta Spotmeter F is a great meter if you want a spot meter that can do flash - 1 degree spot, both natural light and flash. They're only available on the used market, and they're not cheap. For a less expensive option, a Sekonic 408 is a great meter that has incident and reflected, and 5-degree spot via a built-in spot meter, and can do ambient and flash metering. They're also only available used, but they're quite rugged and very useful. I keep mine around to use in the studio, and the Minolta does its duty in the field.
But if you're shooting a Canon EOS body and a 430 EX II, why not put the thing on Aperture preferred and let the camera use the E-TTL?