I got an email with a great deal on Sig p226 .40 cal. My only reason to hesitate it that I don't want to get into .40 cal. I'm already invested in 9mm and 45acp, and don't want to stock .40. The only appeal would be if I could get the 226 to 9mm so the question is...... can it be done? How much $$$ is involved to do it????