318 cam

Also, what mods other than springs will need to be done?
High lift cams mean long duration cams, which leads to very late-closing intake valves which leads to very low cylinder pressure which leads to a sluggish pig of an engine that everyone loves to hate, because it is gonna cost you a convertor and some 4series gears, and she will drink gas like a fish in a lake.
So my recommendation is that you start with available high-compression pistons, and work backwards to find a reasonable street cam, and just go have fun. I guarantee this will be better than stuffing a 292 cam into the stocker,