In my opinion (which you can question and I won't take offense) there are only a couple pump manufacturers that make good PW pumps. Cat (which are super expensive) and AR which aren't and what I have and whatever PW pump you buy, make sure you can change the oil in it. The one I had and the replacement pump I purchased have oil filled crankcases with fill and drain plugs and they all take 30 weight non detergent oil.
All of them are rebuildable (AR and Cat) but as cheap as the one I have is, I just replaced the pump and landfilled the used one.
If it was a CAT triplex, I would have rebuilt it. Mine is an AR axial flow. besides, 7 years and it served me well.
The difference between an axial flow and a triplex is a triplex pump has a crankshaft and the pump head mounts to the side (3 ceramic plunger pumps) with a manifold. An axial flow pump uses a wobble plate to actuate the pump heads which mount on the front. Both do the same thing but the axial flow is much cheaper to manufacture.
Dang Predator engine just keeps on chugging along. Probably outlast this replacement pump too.