[turtlebits]

During my research,

- Recommended from solar forums: https://jaysenergy.wixsite.com/jaysenergy. I haven't bought anything but have communicated with them and gotten a few quotes.

- Santan solar (is where i bought mine from) via ebay (prices were cheaper than their website).

- Craigslist. Occasionally I see posts for people "parting" out used solar panels in bulk.