valve spring selection

hello all, I found a broken inner valve spring on my Dart.
unfortunatley for me, I dont know exactly what cam I have in it, it came with the car.
I believe its the P4120657 Mechanical Flat Tappet, Adv. Duration 312/312, Lift .590/.590.
I did measure the lobes when I had it out and matched the .590 part with my 1.5 rockers.

I have Brodix B1 BA heads, the Brodix site lists:
Valve Springs:
1.550 Roller Valve Spring - GA 1000,
240 lb Closed, 550 lb Open,
1.950 Installed Height,
.700 Maximum Lift
(B1 BA, B1 BS)

but the info I found for the springs for this cam is:
Installed height 1.70”
o.d. 1.45”
lift .610”

any help with spring selection would be greatly appreciated.

*I have not removed a spring yet to measure, I need to make a tool to remove them on car since these heads have different shaft towers than stock.