Evander and Trystan are both under the DMLE umbrella although neither are probably the best as sources? but I also have...

Porphyria Dempsey, Ravenclaw housemate a couple years older and also a spinster with feminist leanings; Jude Wright for potentially meeting through politics things, via Kieran, or ~liberal discussions if she ever visits the ABC; Savino Zabini as a Divination friend, and/or someone who may try to give her info on "crime that hasn't happened yet and may or may not happen" xD