Apparently my parents "Redneck Engineered" a retention device that simply involved attaching the hose from a combination syringe to a 10-oz douche bulb ( It does work if they are Faultless brand, not otherwise).
At first, my parents didn't share equipment, so I don't know how this came about, but Dad was the one with the "faultless" brand stuff so I don't know if my Mom bought the Faultless brand bulb just for that or what. It would have been sold with the wider curved douche nozzle. the bulb still exists but neither the douche nozzle nor the shield has ever turned up.
What they were doing was they were filling it with plain warm water and attaching the hose from a bag and putting the small straight enema nozzle on it. The receiver would be in knee-chest position and would take a 2-qt Epsom Salt and soapsuds enema ( remember that they were both in their mid-teens at this point, about the same age I was when I got my first and so far only 4-qt bag, so 2 qts may have been close to their limits).
Sometime during retention the receiver would hand signal the giver and the giver would remove the original nozzle and quickly insert the nozzle from the bulb. The receiver would start taking slow deep breaths, and as the receiver breathed in the giver would raise the bulb over their head stopper side down and squeeze, then as the receiver breathes out the giver would lower it below their own waist and let it re-inflate. This would repeat until the receiver was confident they could hold it a few minutes longer, then the hand signal was made and the bulb was held upright at the same height as the receiver's rectum stopper side up No attempt was ever made to get the rest of the bulb in. The bulb was at least rinsed between rounds and thoroughly cleaned at the end of the session.
I doubt that Dad knew what a balloon catheter was at that time. He now thinks Mom had been given "more than one, but not a whole lot" of retention catheter enemas by that time but I don't think he ever knew where or when.
That system, while maybe not as good as a balloon-type retention nozzle did a good job for a couple of still young kids playing around with purging enemas for the first time