If they don't chamber the 243 I would get a tikka in 243 I have shot a couple of these in 243 and know they will shoot.Or if you want to save a little money there is the remington in the sps or now they have the varmit sps in 243.I wouldn't mind haveing one of them myself.
I figure you reload since you said 243 AI??
You can reload the 308 with 110,125 or 130 gr bullets,I haven't shot the 110 bullets in my 308 but have shot the 125 and 130's and they shoot very good.
Good luck whatever you choose.
I think the cz's really look good ,if I was going to get one I think I would choose the 6.5x 55 since they don't have it in 260 cal either.