For a tank like this I always recommend getting a skimmer rated for double your total system volume. This creates a safety net in the event of die off or a pollution disaster (as much as we hate to think it will happen to us, it will happen sooner or later). Reef Octopus makes a few reasonably priced models, ATB is always a great choice (but be prepared to pay for the quality), the new ATI Powercone skimmers are amazing, and the BubbleMagus line of skimmers are great quality for the price. The most economical skimmer for a tank like this would be an ASM G5. Some people swear by them, but their performance just doesn't stack up against other brands. In any case be prepared to pay $500+ for a skimmer for a tank like this. The most important thing when planning a tank like this is to buy all the right equipment the first time, even though it adds major expense. It will save you money in the long run as you won't have to "fix" or upgrade your system, and will also save you lost livestock. 

This my reply to a similar thread (below).  I'm all about the Tunze 9002's, and they're well below your budget.  I had a 10g QT with a 10g sump that regularly held ~50 corals (mostly SPS), and a couple fish.  I also had a 55g with 20g sump (technically above the rated limit for the skimmer) - it had tons and tons of SPS with usually around 4 smaller fish. 

 

The Tunze 9002 was like $150 when it first came out, but I've seen used ones for ~$65.  Not sure what they're running nowadays, but I'm sure you can look that up if you're interested.  :)