This is all going to depend on how loyal you are to that price range. If you decide that you have to have INFI, your budget is gone, the BATAC is a 5 inch blade that comes without a sheath from the factory, and costs a little more than the price you mentioned. The Game Warden is 3 inch blade that normally will sell for quite a bit more than the price you mentioned. Swamp Rat knives on the other hand, are backed by the same warranty, and if you can find one in a style that appeals to you, it just might be in the price range you are looking for, and currently sheaths are easier to get for Rats.
If niether one of those choices really "speaks" to you, I recomend that you go over to the custom knife makers for sale area and scout out a style that you like, you really should be able to find one in the price you are looking for, and disregard the fact that the knife sold in ten minutes or a couple of hours, email the maker and ask how long, and how much money to get one of your own. The other advantage to this method is that you can request minor changes to the design, blade material is sometimes negotiable, handle material always is, and length can be adjusted to your tastes
In the end it depends on what you are looking for, there are a few factories out there that really stand behind their knives and there are some online knifemakers who also stand behind their knives, and sell at prices that the factories cant't touch.
Keep 'em sharp.