I actually spent more time looking for stuff than actually building anything. I did however get this far.

Luckily the copydex at the front plinth hadn’t dried so I managed to straighten it up a bit. The one bit you can’t really see is the cereal box card glued to the bottom of the blue foam. This will give it a bit of strength and also protect the corners a smidge.
Next will be the top. Part of me is wanting to do a bit of a ladder and another part of me says sod it, I can’t be arsed.
The smaller pipes are cardboard drinking straws covered lengthways in masking tape to hide the spiral pattern.