I had many lengths of PVC tube at my disposal, but most mounts seemed to be tailored for 32mm PVC tube. I am building a dry box, so designed the mount to fit on the inside of the clear box (see pictures).
The two extended arms provide retention of the PVC tube, giving a satisfying snapping action when inserting the tube. The support can be fastened using M3 bolts and M3 nuts (which should fit snugly in the hex depresions).
The author marked this model as their own original creation. Imported from Thingiverse.