Pretty normal back when they were made to use vinyl tubing and 45* pipe fittings with hose clamps, especially with Sheridan paintguns [so very period accurate]. Otherwise 45* PVC fittings were used most of the time. There were a myriad of different Direct Feed connections and little if any paintball specific "elbows" yet when the Whaler was popular so plumbing fittings of various combinations were normal.
I still use and prefer Whalers on my pumps. Old Viewloader sewer drain loaders work real well too but stickup in the air too far for my taste. I even have a couple of One Arm Bandit loaders that are reserved for a couple of old LAPCO pumps but they are not the greatest feeders and can be a little fragile but are unique enough to warrant being on the Grey Ghost and Grey Spirit.