Wife Satisfaction

Several years ago my wife and I were in a threesome with a friend and I found it very exciting sharing her with another man. It was just a spur of the moment thing and it never happened again but over the years it was in my mind and I have been talking to her about doing it again. She says that she is satisfied with me and doesn't need another man.
From time to time I bring the subject up and she says oh you would like to see another man fuck me huh. This just excites me more and we talk about it during sex. Sometimes she seems to like the idea and other times says she is fat or old. I can satisfy her orally but I know inside that she would like to feek a man inside her.
I think if I found someone as a friend that eventually she might start thinking more about it.
My problem is I have no idea where to look. She might feel safer if he was married but didn't live in our area. Size wouldn't be an issue as long as he could perform and complete the act.