You might consider a lefty Zastavas 223 and a rebarrel. That's what i did for mine. I believe there is is and ejection timing issue with using a Remington 700 223 and going to a 221/17 Fireball. I could be mistaken on that but I seem to remember reading that somewhere and it may have been here.
Here is a link to a Charles Daly (Zastavas) left handed barreled action for a pretty fair price.
lefty barreled action I have three of the Charles Daly actions and have had PacNor barrel two of them. One is a 17 Remington and the other a 6mmx222 which I had stocked by MPI. I haven't stocked the 17 yet but it's on the to do list. They make a trim little rifle.
