I got a combo for Winning Valkyrie and Astral Spriggan
For Winning Valkyrie, you want Disc (1) Frame (Meteor) Driver (Ultimate Reboot)
For Astral Spriggan you want all the original parts other than the armor. Armor (2) Disc (Nexus with D gear) Driver (Yielding)

Honestly I think these combos are questionable. 1 is for Xcalibur, not this, and yielding I think is useless nowadays.

Why Winning Valkyrie? It's too old.