Yeah it doesnt actually take much to convert them. All you need is the heads, an intake that'll fit them, the conversion pushrods from mancini, rocker arm assemblies with plates (which you can get from hughes or from chrysler), magnum specific head bolts (also from chrylser), magnum valve covers (also from chrysler or used), and the throttle/kickdown bracket for magnum intake from mancini (i just bent my LA one a bit and it fit fine though).
Everything else other than that is standard LA equipment.
Don't forget that those magnum rockers are 1.6:1 ratio. I put a factory 340 cam in my magnum swapped '84 360, and the rockers bumped it up to .459/.472 lift with the same duration. It has come serious bottom end to it, idles at 18 inches of vacuum, and moves my W-250 around great. In an A body that motor would fly. I range it at about 310hp. My heads are also the largest valved of the 3 encarnations that came from the factory. I got a SCREAMING deal on them on eabay. 160 bucks plus shipping rebuilt, and they came with the valvetrain, and valve covers (a guy had sold a car before doing the swap and was selling off his swap stuff)

Anyways, I recommend you do it. Its not all that expensive and the power gains are great. Shoot, my compression is even 9.5-9.7:1 now. Plus its still nothing super aftermarket or outlandish like aluminum heads etc. It's still all factoryish stuff.