Finally the decision has been made.

Cuprum-74 said
No, I had to use the positive seals.
Here:

COMP Cams Valve Seals 521-16
Or:
COMP Cams Valve Seals 514-16
I can't remember which. One is designed for triple springs (521)

I found a .530 cutter for cheap I'm gonna do some research and make sure it is the right ones but I will order it and do it myself.