There are thousands of people out there who are desperately looking for a "technical co-founder." Most of them will never find such a co-founder because the numbers are stacked against them.
You have an advantage here -- you can hire such a person as a professional CEO, not a co-founder, and you'll be able to find someone very good if you've got a company already making revenues. Get a lawyer to structure a deal that lets you retain 100% control of everything, and give the new person a 5% equity grant with four-year-vesting and a one-year cliff. Then you decide whether they get to stay, they report to you but can go out and raise money for you, and you get a valuable partner to help you run your business. Over time, if they prove to be an ever-increasingly important partner, you can grant them more stock options.
You have an advantage here -- you can hire such a person as a professional CEO, not a co-founder, and you'll be able to find someone very good if you've got a company already making revenues. Get a lawyer to structure a deal that lets you retain 100% control of everything, and give the new person a 5% equity grant with four-year-vesting and a one-year cliff. Then you decide whether they get to stay, they report to you but can go out and raise money for you, and you get a valuable partner to help you run your business. Over time, if they prove to be an ever-increasingly important partner, you can grant them more stock options.