Yep, I use these 'top hats' a lot, normally I get them delivered next day or with in two days. I think Royal Mail takes 5 to 7 days to post to US for £2.25 ($3). Anyway happy to help if needed.
If your making some, make sure the brushes are a lose fit inside the sleeve. Otherwise the spring wont keep enough pressure on top of the brush which pusses it onto the armature. I've fallen into that trap before!
James
For shipping that's kinda' what I was thinking/ remembering.
And if it is to be made, a sample part could assure the tolerances necessary in these small parts. I think that the tolerances required in small parts are not always recognized until they don't fit or are sloppy and where that difference was caused by a few tenths of one thousandth inch.