Anything flat tappet made for a 289/302 should fit fine. I have one about that size in and it works fine.
I did notice a little drop in gas milage, but I later canceled it out with a new ignition and k&n and it went back up around where it was before the cam.
You will lose alot of low end performance unless you change those gears with that cam choice. The only thing on your side is you are running a 4spd. with an auto it would be worse.