I am not sure if this is a service people need. The people that need mentors the most probably refuse to get them. People that know they need mentors and actively seek them out eventually find them.

Also, you're talking about a small segment of a small niche numbers-wise. Of all the people in the US, only a portion are entrepreneurs or business owners. Of that segment, only a portion are actually successful and will actually be good mentors. Also, how will you qualify the quality of the mentee? No one wants to waste their time, especially if you already have several mentees.