The guy is whistling in the dark for what he wants to
charge to make one. Looks like the whole assembly
can be done for maybe $20, less driver used.

I've made long pipes with PVC but never took the next mental
step to use lots of corner connectors to get the size down
but keep the length.

Only problem I had with mine for the RS 1197 was lack of
soundstage. I felt that some sort of baffle is needed.

• PVC Nautilus