I had green Bilsteins that were way too stiff and on the advice of someone here or on Spyderclub I swapped them for them cheapo KYB’s (not the gas-a-just) and couldn’t be happier.
I think someone makes replica Konis (Ikons) that are valved for Speedsters and Spyders, but I have no experience with them.
I think there’s a company that will rebuild vintage Konis with Speedster/Spyder valving but it’s really expensive if you don’t already have the vintage Koni cores to rebuild and only certain shocks were rebuildable.