Similar story, I replaced my OE with the Remco Power RV Series Aquajet 5.3 mine did not have an accumulator tank. I too could not get parts for the old leaking one. I installed w/o a check valve. Loop hoses as it was. I will tell you this these pumps are rated potable drinking water safe because they have orings and diaphrams made of different material than a typical general purpose agricultural pumps which are less expensive. Others I’m told can get bacteria and other not so friendly growth on them. That’s why the correct pumps say drinking water safe or potable water safe. To get the warranty you have to purchase from their sellers like CW and other rv centers. Best price believe it or not was at CW, I purchased in FL $224.00