Ways to find/obtain Praon pequodorum?

I'm a senior in college doing independent research on insect agroecology in SE Pennsylvania alfalfa fields, specifically with biological control of pea aphids by predators and parasitoids. I plan to work with Orius insidiosus, Aphidius ervi, and Praon pequodorum. I already have a good breeding lab colony of A. ervi from pea aphid mummies collected from the alfalfa field my lab works in, and we've ordered commercially bred O. insidiosus, but I've not yet been able to successfully establish a viable breeding lab colony of P. pequodorum. The few P. pequodorum that I have been able to obtain and attempt to establish a colony with were from cocoons I found in one of our aphid colonies from aphids we collected from our field, however there were not nearly enough to establish a sustained breeding population. I've gone to the field itself to search for more cocoons but was unable to find any. I know A. ervi and of course O. insidiosus are available commercially, but I don't think P. pequodorum are as far as I know. Does anyone know any good ways to find and obtain enough of these insects to establish a lab colony?