hi Rafon, so what do you consider would be the aspects of the "poly lifestyle" that you would be interested in? Being poly means so many different things to different people.
Is there anything that is important you about this female other than her age? Like whether or not she is in a relationship already? How close to you she would need to live (some people have different requirements for distance)? What about if she has kids or not?
I think that the more information you can give here, the better chance to have of finding someone that suits you, rather than having to deal with a lot of folks for whom you have no interest.
"Listen, or your tongue will make you deaf." - Native American Proverb