Tip of the hat...used parts suppliers

If Beemerboneyard doesn't have what you need, search at Motorworks. I needed both rubber boots for the '05 1200GS rebuild and was able to get both (1 new/1 used) from Motorworks for 1/2 of BMW's list price, including shipping from England. Essentially, if you find what you want is available, create an account, then send an email listing the parts you require. They create an invoice and post it to your cart. You log in and complete the transaction. Easy peasy.

I bought a used drive shaft from James Sherlock's Ebay store as well. The merch arrived today as advertised. Can recommend based on 1x experience.

Thanks for the tip.