About C. Simoni, I found very confusing info. Some people are sure, that they are to be kept in acidic water with gh<1. Others say that they are shrimps that need salty water to procreate, so they are not to be considered as a species well cooping with soft acidic surrounding. I for that matter was told not to get them for my aquarium, as they are supesedly not good for BW tank.
Still I think, that if some Paros are offered as WF individuals, than it shouldn't be that hard to get some of those shrimps. Even if Paros keeping and breeding is a small niche, it should be enough to keep tem for "own purposes". If WF Parosphromenus cost around 50zł - 15 Euros, than how expensive could they be? 20 Euros for a starter colony?
I think that this is the move to be considered.