Did the Greeks ever adopt foreign equipment ..

[Ghostmojo]

When the great Keltic invasions occurred there must have been some effect upon Greek tactics and equipment?

The adoption of the Thureos is thought by many to be a direct consequence of this, though I must admit I am curious about a route directly from Italy Via Cleonymus, Pyrrhus or the other adventurers.

That is exactly what I was getting at. Mind you perhaps by then, regular direct interference in overseas territories was more common - which helps link the Italiote, Epeirote and Lakedaimonian aspirators; but the Keltic (or Celtic) intrusion is an interesting one. Of course The Spartans had used Keltic mercenaries before (supplied I think by Syracuse?) and these peoples may well have thought about returning to Hellas one day - but not as paid fighters - but as potential conquerors.