I was a victim of the dreaded "Leak down chair".
I flipped it over to get the lay of the land. The cylinder was 1" diameter, so a quick trip to the band saw with a piece of 1" I.D. PVC pipe was in order. I sliced a 2" long piece and then split it. Quick work on the band saw.
Attached with a couple of zip ties. The first was a little too short. I made a 2 1/2" and a 3". Installed the 3" and it seemed just right.
I used 3 zip ties, but didn't cut them, in case I need to snug them up later.
I thought it would need heater hose clamps, but the zip ties are holding OK.
I then drew it up so it can be 3D printed. This part is 1.125" I.D.