£11.96 here for a decent quality Oriflow one, free economy delievery or £3.99 next day. How google finds it I have no idea because the description doesn't mention brush,washer or Oriflow and you can't even find it if you search their website.
You could get a local wood turner to make a handle which is hollow for the tube and a suitable recess turned to suit what ever cheap brush head you want to use and can replace easily.....
I fully understand that everyone has different financial priorities but surely it's not worth messing about with bodges and work arounds when the proper thing for the job is £12 delivered?
As a result of this thread I ordered these from the link I posted.
They are very nice, stiff bristles and strong handles. These are the proper job.
Even though the description said Trade Quality no mention of brush anywhere google found them. I then wondered if they did the none hollow ones, I incremented the part number by 1 and guess what I found the other style.