I some locales, there are elements of the fetish/kink community that engage in impregnation & breeding, from fantasy/role-play to fantasy/realization. Usually these small community circles have an intro and vetting process. The form these take varies. The circle I'm part of heavily vets the males that participate, including requiring fertility testing, STD/STI and genetic screening - a surprisingly large (given the demographic) contingent of female participants are married, seeking to be impregnated (or bred), carry the ...... to term, and raise the ....... Their reasons/rationale varies.
In these circles, impregnation is treated differently than breeding. The former is usually on the basis of selection, and some sort of intimate/erotic/emotional connection between the impregnator and the impregnated. The latter is perhaps more out there; breeding usually combines group sex with the impregnation target, in the form of a gangbang - the center is aiming to be impregnated by a random, unknown male, one they have no relationship with. The number of intact, fertile males participating leaves uncertainty about who fathered the ......, as opposed to the certain knowledge in the impregnation scenario.
The circle I participate in has a core of intact, fertile males - "Studs," who service the females who desire to be impregnated. There are two vasectomy-safe males (I'm one of those two) who are invited participants, based on certain skills and services they provide. It is one of the edgier kinks, and pretty rare. I don't know if your local fetish community has anything like this going. It would take an intro from a trusted participant, screening/vetting to become involved.
There is significant legal, moral, and ethical consideration in all this. Paternity suits, emotional risks, and so on... tread carefully along this road, particularly if you come across a random couple looking for another man to father their .......