Good engineering and execution costs money, that would be my guess why you can't find anything. I'd also venture to guess that the restrictive nature of most automatic knives throughout the states also contributes to their high price.
Save your money, or look for a side opening automatic. Pro-tech makes a bunch of more affordable autos. Remember, you don't want to waste your money on a piece of junk, quality costs money.
Have a look in the automatics subforum.