My Logitech wireless headset, an H600, is having difficulty holding a charge. I found a Youtube video explaining how to open it, though I'm not entirely sure why it takes 22 minutes...

Anyway, it looks like I need an AHB521630 battery. Searching for this returns a number of B2B suppliers, mainly out of China.

What's the correct form for buying one-off items like this from these sites? Do people have a preferred one?