Crafty Kate is your best bet. I have no 'Maid of Colchester' in any of my indexes, including the alternate titles for CKoC. Apart from broadside references I have no British oral versions but plenty of American ones. Those with tunes are in;
Gardner and Chickering, B&S of Michigan
Trad Songs of Nova Scotia
Folk Songs of the Catskills
B&S of Utah
and of course Sharp's Southern Appalachian volumes.

The story is reused in 'Poor Nell'
The early broadsides seem to be related to an even earlier ballad 'The Politick Maid of Suffolk'