I don't really know what kind of sound that is, but as far as size, I'd say a good half stack would do it. but, I'd try to get something with a line out on it, so that if you need to, you can plug into the PA just in case the amp isn't loud enough.

I had a 100w fender 2x12" and it was loud! I played gigs for about 40-50 people with the volume at about 2 1/2. of course, 7 wasn't very much louder then 3, 3 was about 5 times as loud as 2. I think a good 100-200w half stack would do it for you.