My G G Grandfather made pump organs in the town of Rothsville, Pa. He went to Philadelphia and Baltimore for the reeds and perhaps some other parts, but he was a master carpenter who also built string instruments. I have a cello and a violin made by him. There are newspaper notes about organs he made for others. As far as I know this is the only one extant, but who knows? This may be a way of finding others. You can see more about him at https://www.findagrave.com/memorial/34978354/john-m-fry

The organ descended to me in Spring of this year. My husband and I completely tore it down, and with the help of the facebook group and Horton Pressley's book, we rebuilt it. Previously, a couple of keys kind of worked. Now all keys work and the bellows, which was rebuilt twice, is great.