Any speed 40-0 sized brushless motor would work well. You could go direct drive with a lower Kv motor. An example would be a Mega 1615/7 direct drive. You could go with a 9 x 6 prop and a 3-cell Lipoly battery. My personal favorite would be the Hacker Motor systems that we use on the Renny or Hyper 2ME
Here is the web address of the Renny 2ME to see this motor system:
http://www.nesail.com/detail.php?productID=1273 This is my personal favorite as it has the least weight and highest performance but is a bit expensive.
You could go with an outrunner. For example, a Hacker A20-20L can move a 9 x 6 prop and give you 33-35 ounces of thrust.