What SWAY BAR to choose

there's a lot of options you have here and it really depends on how nit-picky you want to be and whether you're okay with welding mounts.

no matter the way forward, you're likely going to have to swap your spindles side to side to go rear mount on the calipers in order to avoid interference.

with choosing the option to go with the 67~72 LCA's and stock tabs, you can run a stock style bar from just about anybody: hellwig, hotchkis, firm feel, addco, quickor, sway away. all have their pros and cons: expense, clunky hardware, diameter/rate choices. you will 100% have to do the spindle swap boogie, but that's probably the "cleanest" install with that K and those brakes.

with what you have now, 69K & 73+ brakes & LCA's, the hellwig bar would be the easiest install. it's a bolt in and uses the lower shock mount to locate the tab. so it's a little ticky-tacky that the stock tabs will still be on the arms, but if you can live with that it's the easy button here. the bonus is that you *may* not have to do the spindle swap boogie and it tucks up a bit better than the hotchkis bar. i don't like the hotchkis bar here because you have to weld on the mounts.

at the other extreme end of things is swapping out the K to 73~76 style and updating so that you're running all one system. it's way more work and investment, but a more cohesive combo and then you're back to dealer's choice on swaybar selection.