for a street 427 it is very hard to beat an original ford grind,,the AA or B I belive it is,,these are worth checking out,,
I have roller rockers,,but flat tappets,,it seems to workout good,,the wickedest motors I have even driven were 427's with ford flat tappet cams,,solid {hollow}lifters with extra long push rods,,this is an inexpensive and bullet proof set up, I understand if you like the best,,or high tech,but truth is unless your squeezing hp,,rollers arent worth the out lay,,racing engines are a different story,,BTW,,in a center
oil engine,you have lots of choices,,428cj stuff,,etc,,but in a side oiler,must use side oiler cam,427s are hard to mis cam,,as long as you stay in the shorter duration numbers with pump gas compression {10.5} or below.this puts BIG torque near the bottom end,,versus mid to high,
hope this helps,,tk