Ask HN: Two prototypes developed, how best to find a business co-founder in US?

I've two prototypes which need sales done in US to test the market. I'm from outside US. One is in the fitness space and another in the tuition space. I'm considering finding business co-founder in US but I'm not sure where to start and I want to avoid having a business co-founder who couldn't do sales. Any advice from HN?