oversizing a skimmer isn't really the best thing to do. If it's too large, it'll skim for about a day and then there will be nothing left to skim therefore starving your corals of nutrients.
that said, take a look at the aquamaxx WS-1. it's a cousin to the HOB-1 which is a proven skimmer. If you want something larger, take a look at the bubble magus Curve 5. I had one on my Res Sea 170 and it was way too much skimmer.