What are these called?

The cup-like thing that goes above and over (covers) part of the spring, before the retainers and keepers.

http://www.geocities.com/sdampier@sb...g_002_copy.jpg
http://www.geocities.com/sdampier@sb...g_006_copy.jpg
https://www.racerswholesale.com/imag...MOR/67700T.jpg

We called 'em oil shields. They are meant to be used with a small o-ring on the stem of the valve. I think you'll find the o-rings under Sealed Power #MV1233.