Want another kid, but I'm single

For single women, they can get a sperm donor and have a baby. But what is the equivalent of that for men? Does it exist? I have one kid and he's very social. I have a decent relationship with his mom, we co-parent. I'd like to have more kids, but I've been single a while and I don't really see meeting someone who wants to have kids; the women my age (40s) are pretty much done having kids. via /r/Parenting https://ift.tt/3iR5rks