I've bought from HD Custom Guitar Supply, most recently the Supertone for my EB-0. One guy in a small town in far northern Wisconsin. Usually a little less than other sources, free and fast shipping.
My information is that the owner died a couple of weeks ago, he was only in his early 40s, and that the business will be discontinued. Almost everything in his Reverb store is discounted 25%, at least for the next 7 days. Most of it is guitar parts, not bass, but there's a lot of major brand stuff including Bartolini, Hipshot, Tusq etc. If you need to stock up, now's the time.
https://reverb.com/shop/hdcustom-guitar-supply