Welcome to BLF.
I would look into known flashlight stores, like Kaidomain, Intl-Outdoor or fasttech. Amazon is fine as a platform, but you’ll typically get a bigger selection in the stores mentioned.
Also, you can select any LED on any “base” that fits your light, as long as the driver is compatible (or the right one purchased) and the battery voltage is in line with your expectation/your light.

Here are a few links:

www.fasttech.com

http://intl-outdoor.com/