Agonizing over those prices doesn't help. If the lens is truly needed/wanted, one might as well start looking at the economy of different alternatives to buying it new, such as:
* Used 300 f/2.8 IS lens on the F&M B/S board.....there are still decent deals to be had.
* Used 300 f/2.8 non-IS. Here and there they pop up on the F&M board. Also, places like KEH have had 7-8 copies now for months. They are on the expensive side, however, one gets a good return option + 60 day warranty. Also, one should check Adorama used lenses as well. I consider their prices to be a bit better than KEH's, and so is their service.