Q
Price of Luther & POW appear on a Deeming, Boston, Mass. broadside of about 1840. On the earlier Swindells and Batchelor broadsides c1820 they have King of Prussia and POW.

Of course these are not names in the 16-17th century versions.

Richie,
Chappell is somewhat confusing. He keeps referring to 'the second part' and there are several second parts. When he refers to 'the second part' in his introductory note I think he means the whole traditional ballad which of course itself has 2 parts. There was apparently another first part partially given in the play 'The Noble Kinsmen'. This would imply that the ballad as it was registered in 1594 was the one reprinted in the 1650s, and the one registered in 1590 was the first part not included in the later printings and having a different format without the refrains.