Aside from what I've found cyber stocking the most popular bonsai sites, does anybody have any great sources for containers / pots?

Try: https://rockymtnbonsai.com/index.php/bonsai-vendors/bonsai-pot-vendors/

Check out Wigerts. they have some good/large mica and plastic pots

www.wigertsbonsai.com

There are a decent number of pots posted in the bonsai facebook sale groups regularly. I also have gotten pots from each of these folks, at different times. Just depends on what you're interested in spending I suppose.

https://www.etsy.com/shop/bentpinepottery

http://earthwares.org/

https://www.ikerbonsaipots.com/