Battery:
https://www.aliexpress.com/item/Europ...

Bike kit:
https://www.aliexpress.com/item/100km...

Frame, all other components(you have to directly contact and speak with the supplier, the lady you will talk to is very kind she will explain all the details, she helped me a lot, you might need to negotiate a little bit to drop the price to 100$ for the frame):
https://ebikesmotor.en.alibaba.com/?s...

A similar bike:
https://www.aliexpress.com/item/2017...