Do I need new rocker shafts with new rockers?

I bought some (used) Ductile Iron adjustable rockers, will these work on my used stock shafts, or should I get new ones? I rather not spend more money, but if I have too, I guess I have too.

Also do you know if these need springs between the rockers on a small block? I know they do for a BB. I know I can do a mock up, but thought someone might have an answer if the mock up still looks to be "iffy".

Thanks much.