I don't know where they are, but the Troy reference is just a classical allusion. If you look at Lyr Add:Claudy Banks and go to the 1st of the Bodleian links Malcolm provided, you'll see the verse:

Oh if my Johnny was but here he'd free me from my care,
But he is in the field of battle, dressed in his uniform,
He is in the field of battle, his foes he does defy,
Just like a prince of honour bright, who fought the wars of Troy.

with more or less the same in the other.

You'll also find other broadside references in The Folkinfo entry for Claudy Banks, but I haven't checked those to see how many include the Troy reference.

Mick