Spacers basically identical to mine are visible on some of the bikes offered by Peter White Cycles. The only difference I see is that he has also tapped them for a dynamo headlight bracket. See the 4th down photo of the silver grey Silk Road just above the frame specifications tables A similar spacer, dark painted, is on the dark green bike with Brooks saddle shown further down the page.
The idea is so obvious to me that I am not surprised that someone else did it first!
--- In email@example.com, David Dannenberg <ddannenberg@...> wrote:
> Send us a picture!