I really don't have anything other than the reference seen below.  This was found in The Book of Brennan, a wonderful book of notes and drawings compiled by James Brennan and published by Chris "Doc" O'Melvin.  Brennan was believed to have made Uilleann bagpipes from about 1900 to 1915.  Drawings and notes suggest that he might have made one or more GHB as well.
Makers of Old Bagpipe Place Home
The Bagpipe Place Museum