This might muddy the waters for you, but I found a William Eager here:

Letter dated Dunbar 4 Sept 1650, Cromwell to Lenthall, Speaker of Parliament. Annex’d to this Letter was a List of the Names of the Scots Officers taken Prisoners in this Action; But it will be sufficient for our Purpose to observe that they consisted of one Lieutenant General, three Colonels, eleven Lieutenant-Colonels, nine Majors of Horse & Foot, twelve Cornets, four Quarter-Masters of Horse, and seventy-eight Ensigns. As all below the rank of captain were liable to be sent to the plantations, there are 171 names on this list of that rank.

I posted the document here:

http://dl.dropbox.com/u/33221384/Dunbar.pdf

Some history:
http://www.geni.com/projects/Scots-Prisoners-and-their-reloc...

Rex