RB and a roller Cam

If you are rebuilding the engine, another few changes while it's apart is no big deal.

If you are only expecting to perform a cam swap and have everything just work out, calling someone like Hughes Engines might be a good option.

I know a couple of guys whom have purchased valve train items from them, they definitely have Mopar B/RB down to a science. This is where my roller valve train will be coming from.

I agree with Hughes, I ran several of there flat tappet cams over the years. The last one was a HEL 7680 with 1.6 rockers in a 446 Scamp that worked real good. Ran 6.35-6.40's.