There! I fixed the picture, sorry about that.
Here is a source for the Carry-Tubes here in the UK.
http://www.euroffice.co.uk/search/?term=Carry+Tube
I'm sure there are plenty of suppliers in the USA.
The home made versions I saw on another BB were made with
Plastic plumbing pipe and seemed a bit heavy and cumbersome.
This is made with fairly light guage plastic and if it
only lasts a few seasons, it is fairly cheap.
I have done quite a bit of DIY tackle making in the
past, but I am getting too old to be bothered now.