I don't know where you get the $630 price for the Erson roller rocker set up i just bought mine at Flatlander Racing for $595,and they have help a TON! with my FE motors they have been building them for over 40 years............
I also was stuck with a breakdown of my Mustang motor(cam problems) they sent shell lifters and pushrods the next day.........Im on the road again!