Hi Tom,
Thank you for the tip.
I do watch the auction site and they are usually available for 30.00usd and up.
These are really a convenience rather than a necessity so those b.i.n. prices are prohibitive for my budget.

Your post did cause me to see a new listing I hadn't been alerted to that has a set of 3 that will be reasonable if the price doesn't climb too much higher so thank you.

The AM-1 is a metal reloadable cartridge for bulk loading that fit the F2. They have a model that fit the F and rangefinder cameras that are more abundant and can be had for around 10usd if you shop carefully.
Leica makes at least 2 different sizes, one for the Barnack bodies and one for the M series and as you probably guessed are quite expensive.