Cyanta
I'm glad you're back and ok!, it's been so long since the last time you updated, thank you for the chapter and as always.......FIRST!!!!
The reason why Artoria can only have Excalibur as a weapon is because she is still technically alive, so only weapons that are immediately at hand could be available for her as a servant. Since this Artoria is truly a summoned spirit of the dead it wouldn't be unreasonable to also have in her possession: Caliburn; Carwennan (dagger with Presence Concealment properties); Clarent (ceremonial sword stolen by Mordred); Prydwen (shield/surfing board, also stolen by Mordred)