how do you want the car to sit? low? super low? stock-ish? a little rake with the *** up? how much wheel/tire do you want to show?
have you test fit the rims and tires? do you *need* it to sit at a specific height so that the tires don't rub anywhere?
i know this all seems very particular and overwrought, but all of this has a bearing on choosing springs that will work.
as a
somewhat educated guess, if you're not fouling the tires anywhere in the wheel wells and you're okay with it sitting at slightly lower than stock height i'd order up these:
1967-1976 Dodge A-Body Geometry Corrected Leaf Springs
the main reason is that i know they'll be decent quality, they come with the bushings and new hardware, and they're listed at 130 in/lb rate which is about what you want for street handling and to compliment the front t-bars. they also have a half leaf front so the forward section will be stiffer and you may not need a swaybar.
but as mentioned above, you could call espo and talk to them and see what they have to offer and that would give you another option.