They should try to partner with a manufacturer and run the line again.
If someone who is good with CAD can make conversion kits for airsoft guns. And the community is able to get the attention of an airsoft company like classic army. We can make a case that if enough of us want this we have the files ready and they can say if x number of people want it we can do a production run there pre order so everyone has a stake in this and see what happens. Possible though probably very simplified and optimistic but just a thought.