E-Bikekit.
www.ebikekit.com
+1 866-882-3245
They used to have an on line chat on the website, but then I retired from that job. EBK is known for having a kit too expensive for most people. But they have a real warranty on the kits and batteries, and sell batteries that are actually legal to ship. They are located in PA, near Philly. These guys have been around for more than ten years. The wheels are pretty sturdy, hand built in the shop using good spokes and rims.
On the downside, this is still covid times, and getting product here to sell is still a problem for all vendors of every product. Normally they would have everything in stock at this time of year.
Buy from any of the three vendors now suggested, all three have quality, legit, product. The ones to avoid sells a large battery for only $400 bucks, and then ships it labeled as something else, toys, power supply, etc.