And here we have the finished article. The base is just a pill-bottle top, with a couple of washers underneath to give the base some weight. Looks a...
And here's the rack from a couple of angles. I didn't have any countersunk self-tappers, so the screws are proud. I've added a couple of spacers (rubber grommets, steel washers - anything will do) to the mounting screws to give some clearance.
There are all sorts of permutations to a gadget like this. The main thing is to use what you have to hand.