I mean, Gawain does have his Belt in GO, and the Nemean Lion's pelt is one of the various NPs folded into King's Order. While King's Order as a whole is not compatible with God Hand, I can totally buy summoning Herc in a different Class would net him the pelt alone on top of it.
Just imagine it, Archer Herc with long range Nine Lives and Anti-Civ memes on top of God Hand.
As for your question, technically Achilles did have his Hephaestus-forged armor, but that seems to have been waived away completely in favor of Andreias. Not particularly surprising since 'Achilles' and 'invulnerable' practically go hand in hand nowadays.