Hi Bartian,
I don´t know what tips or contacts you got from Peter but I
can name you two possible sources. But the best will be to get them
from a private breeder and I guess Peter knows best where to ask.
Rifwachter in Hilversum had once P. nagyi when I was there so maybe they have sometimes
Parosphromenus.
On the dutch Labyrintvissen Forum is a guy called Armin who offered
Parosphromenus from a wholesaler. If you check there Soorten aangeboden you can find his
contact information.
groetjes
Volker