A little more oomph

Garrett Ellison said
Headers or magnum right side and 340 exhaust manifold. Is that the solid or hydraulic .470 lift comp grind? I personally don’t look at the 302 heads as an much of an upgrade, as noted by @MOPAROFFICIAL. I would wait for the speedmaster Black Friday sale and see if they have one this year. But if hanging with iron, your combination looks like it could make use of some 360 heads milled enough to at least maintain what compression you have with the right gaskets. What kind of ignition do you have on it?

Based on the above post..
I'd either go like you said SM AL and do some more angles to pick up the lower mid lift numbers or SM Mag and do the 1.94's & chamber deshroud. Al would do 250's cfm and the sm mag about the same.
In that flow range both take about the same work almost. 302 are crap without proper work done to them, more work than results warrant if max power is the goal.