I can't do it all myself, how do I smartly outsource ad sales?

By complete accident, as all great things start, I stumbled into being a publisher. I spent most of my life in journalism and writing, but grew tired of it and started building a distance from the industry. I guessed I missed the business because I started writing about watches, another thing I like.

Before I knew it, I had a newsletter called It's About Time that completely blew up. Like nothing I did before. It's read hundreds of thousands of times a month and it's respected by people who work in the industry.

I'm just one guy, so I need help with this. I've had some help getting advice from this community, so I thought I would try again, even though it's not an issue a lot of indie hackers encounter.

I want the newsletter to be ad-supported. But ads that go a bit deeper. Since this is a one-man operation, I need someone to sell ads. And I don't want just banners, I want to sell native ads that will provide readers with great content, while being clearly marked as ads.

Has anybody had any luck outsourcing something like this?

Another major issue is this newsletter is bleeding me dry, as it got big through very popular, but expensive, giveaways. I don't mind it at all, but it would be extremely difficult to put someone on salary in a sales position just yet. I was thinking a revenue share of ads sold would be a fair thing for all sides? Am I mistaken?