Please be aware that what you are asking for is basically a historical consultation service where other people do research vital for what can only be assumed to be intended as a commercial product for you. As many historians have a lot of work to do, they might be more receptive to helping you out if instead of trying to solicit their service for free, you offer appropriate compensation for their time and work. Going rates for historical consultation depending on the country you are in, the amount of time required, and the level of education of your consultant can run you anywhere from 25$ to 100$ USD and hour.

Thank you!