Excellent question this is. I don't know the urostomy materials at all, but I went a different direction with ilestomy supplies. I'm the environmentally distressed type who cannot believe how much having an ileostomy has contributed to my carbon footprint. It may sound bourgeois, however it really bothers me. There is a company in Plainville, Connecticut, Perma-Type which makes old school vinl and rubber durable medical equipment. I ordered one to my specs with the hope that a reusable item might be beneficial to my quest, but alas, it was nearly impossible eto clean effectively, and the hoped-for seal was awful compared to the decades of research and development that the big three (Hollister, Coloplast, Convatech) has committed to the single use bag business. Some lovely British folks, who own Ostique in London but are in early stages, and another UK company, Salta Health Care, had way more creative ideas.
Let me hear what you are up to with this. I would be happy to locate some 3D printing and guinea pig for the cause. I know that the output issues are more widely variable that sometimes we consider, but think this is a truly worthy project. Godspeed to any innovation.....or creative efforts emanating from the trenches. Local control....has its merits. Best, Ninja in Cali