Here is a photo of my homemade queen marking tube.
This is made from a pill bottle with a non child-proof cap, a piece of cardboard (single-face corrugated wrap would be nice),a piece of netting, a small slice of light foam rubber, and a piece of paper to dress up the plunger, some tape, and a dab of glue.
1. Tube is much lighter (8.7 grams as opposed to 24.3 grams)
2. The plunger goes straight in without wobbling about
3. The foam I used is less dense (compresses with approx. 1/2 the force)
4. The plunger is hollow (two wraps of cardboard), so the foam can flex downward