The Broadwood version is in the Folk Song Journal 19, p123. It was reprinted in Belden's article mentioned above as version B1. Title Lord Burling's Sister.
Richie I'm confused by your request. You are the one who found this version and pinpointed its source as near as anyone could on the evidence given. If you mean where is Tunbridge, I already explained. See 4th May 5.24 pm. But as I said, this is irrelevant. It's obviously just a mishearing of 'near to Bridgwater' as in other versions. You already have the date of the publication. On so little evidence it's impossible to give it an earlier date.