Valve Spring - Broken problem found

I finally had time today to go wrench on the 340 head. I didn't pull the head and used the old rope in cylinder trick to hold the valves up, so I could change out the springs in cylinder #2. Swapped out both springs for that cylinder with the Melling vs-1120 springs. The rocker and valve tip were fine, not all chewed up.
Put it all back together and it has gone from running like an old grain truck to running like a champ........smoke, rubber and sideways through 1st & 2nd :lol:

I would like to get a 2nd set of heads right away, rebuild them and slap them on though, for peace of mind that other springs are not going to fail. I think Edelbrock heads are overkill, until I decide to rebuild the entire motor.
What are some good quality parts to rebuild cylinder heads with?
-The Crane part # 69308 spring & retainer kit should be a quality part, but what about rockers and all the rest going on the head? Any suggestions?

Thanks in advance