I encountered the bagpipes at the top right at the Schenectady Highland Games ca 2000. A band in Connecticut found them in the band closet being ignored. Of course, they look like Henderson bagpipes, and they are for all intent and purpose. They were stamped “Williamson” between the cord holders.
“Williamson & Jeffray” are listed in Jeannie Campbell’s book as making bagpipes between 1948 and 1950. Both were employed by Henderson bagpipes prior to this time. Both Jimmy Williamson and James Jeffray were turners at Hendersons and continued to make a Henderson bagpipe thereafter.
The two bagpipes with the white background came up at auction in October 2018. I watched as a good friend in Scotland was able to make the purchase. He was later approached by the seller, who introduced herself as Jimmy Williamson’s niece. This had been Williamson’s personal bagpipe. The bottom five pictures of that bagpipe, which I suspect was made by Peter Henderson.