How to find Android watch PCBs suppliers?

Hello guys,
I’m looking for PCB supplier who will sell just bare PCB without a case and peripherals. Is there any way to buy it directly from factory? I know that there are just a few companies in China that make them. We need to make our own watch based on built-in specific software and make it smaller & more rugged than other devices on the market.
Any help will be appreciated!

The pcbs used in most android smartwatches are designed by Wiite while the recent android 9 watches have pcbs from HEBS
I don’t know whether they are willing to sell only a few pcbs, but you can try.
There’s also a lot of samsung gear s3 pcbs available on aliexpress.