I located an alternative source for the BangleJS charging cable: Amazon.
There are other sources out there too, I used Google Search Term of "bangle2 charging cable". I chose
Amazon (rather than the raft o' Chinese sources) due to the free shipping and also 'cuz I trust
Amazon to allow returns if things don't work out.
Charging Cable for Bluetooth Smart Watches (4 pin)
Cost is $8.99, I have Amazon Prime so I didn't pay shipping. I got it within 2 days (ordered last Wednesday, arrived Friday).
I checked with Gordon (maker/designer of the watch) and asked him before posting this.
He himself hasn't verified that it works, but I recharged my BangleJS2 yesterday.
I explicitly asked him if it was ok to post this since it means people may not order the cable from him, and his response was:
That's great! Yes, please go ahead and post!
You don't have to worry about taking money from me - I don't really
make anything from cables and stuff like that anyway, they're just
sold as a service to existing customers :)
Thanks Gordon! Really reflects a person who's got the true Open Source spirit!