I agree building myself is the only way I will get exactly what I want. It has been a hard slog.
The former for the pier is a section of conduit I think used for laying underground cables. The interior diameter is about 12". There is a plastic pipe suppliers near where my father lives, and he get offcuts that he usually uses to make containers for plants in the garden.
At first I was not keen on the ribbed exterior, but I can put up with it.
-------------------- Orion Optics UK 350mm Dob
Celestron 8SE
Bressier R-127L + minus violet filter(F=1200mm achromatic)
ETX125
Revelation 80mmED
W0 ZS66
EQ6 Pro
DSI I