UTA case

I'm making a "hat box" for my UTA. I'm looking for a material to make the lip of the lid. K and B's book says to use cardboard but I would like to find a better solution. The lid diameter is 20.5" which makes the total length needed about 64". I'm good with wood, but I've never bent it. I've thought of mat board, but can't find it in the correct thickness or length and I only want one seem. I have a piece of PVC lattice long enough, but it is 3/8" thick x 2" wide and a little stiff trying to wrap it around the disk and it is white.

So would the PVC work? I was thinking of small screws and washers around the diameter for trim and to help hold the PVC while the glue is drying. So a bunch of questions:

Will PVC glue to wood? I'm using Titebond Ultimate wood glue, but could use contact cement. Will PVC get too brittle in the freezin' great white north? I've never painted PVC, will paint stick to it? I want to paint the completed hat box black, put three feet on the bottom, and make it double as a small table so it needs to hold up to dew and those cold winter nights. Any help is greatly appreciated. If you can, post a picture of your UTA case(s).

Attached Image:

Here's a shot of the assembled UTA the case will protect, minus the hardware and kydex.

Attached Image:

How about the vinyl mats that go under desk chairs. Thick and tough, and just leave the screws in to retain it in place.
Just a quick thought
Buck

Jim,
As per Dave's suggestion to make a smaller ring to glue to the lid you could instead glue it to the interior of the bottom portion and use the sonotube as part of the lid as the picture shows.

Bob

Attached Image: