if anyone thinks they can help me or the rest of the internet who might be looking one day find these damn cleaning beads, I made a thread on r/HMF please leave your comments! https://www.reddit.com/r/HelpMeFind/comments/1pskkwf/hmf_stainless_decanter_cleaning_beads_that_are/
@earthshine This may just be the madness talking, but would air gun pellets work? They come in various shapes and differing levels of pointy-ness. I did have a good look for the irregular beads on UK sites but no dice.

@Kyu those are made of lead generally so no... maybe copper ones?

I found some bicone steel beads for jewelery making which are about 4mm across which I'm going to try.

@earthshine Ah nuts. I just remembered the vague shape. Yes, lead is likely... not ideal. :P