5.7 Valve spring seats

[70chall440]

I am in the process of swapping a 6.4 cam into my 19 crate 5.7, part of the swap is to change out the springs. I purchased the Mopar performance 5.7 springs and went to install them, the drivers side (left) was fine as it has 1mm (.040) shims however the right side has locater style seats which my new springs will not go over. I have searched the internet for new (flat) seats without success, I can find a new spring with a shim as part of a single spring replacement kit but I cannot find the flat shims. I have checked all of the various cam makers for shims, seats and locators and while I can find plenty of shims and locators, none of them will seemingly work with what I have (or at least from what I have seen), here are the various numbers for anyone interested

Spring pad on head OD = ~1.500
HP spring ID = .850
Valve guide OD (where shim/locators has to fit over) = .804
Thickness = .040 (measured from the left side)

I appreciate any thoughts, advice, suggestions, or help.