Well Its true you can't, I think you should ask some existing Dating service for affiliation. This might not only provide you with the string of clients, but an existing data base could give you some customers also. All the Best for this project. Thanks.
Are you using an existing dating script, or are you building this site yourself? If you are using an existing script, there are probably databases you can purchase for this particular script. I would just do a search, or contact the software provider. If you are writing the script yourself, there are often posts in here where members are selling databases that you can modify to fit your site.