Well, instead of moving all the other switches to right, you could move the first column to the left, couldn't you? Nav keys would then also need to be moved to the left. A lot of switches for sure, but less than the whole alpha section and not staggered (I don't know if that makes a difference). You would then probably need some extra PCB on the left, and if you are fitting it into a tight case you would probably need to remove extra PCB on the right.
But to all ISO guys I would recommend getting left column keys from m0118. I thing those would work. Then it's just a matter of having the right switch position for the enter key.