Straight Answer First
If you searched for a "JCB bulldozer hydraulic pump," here's the honest answer: JCB's product range — over 300 machine types across backhoe loaders, excavators, wheel loaders, telehandlers, forklifts, site dumpers, and Fastrac tractors — doesn't include a crawler dozer. This is a genuine gap in JCB's lineup, not something we're unable to source. JCB is closely associated with excavation and earthmoving in general usage (the word "JCB" is even used colloquially in the UK, India, and Ireland as a generic term for diggers), but a true bulldozer isn't part of what the company actually builds.
JCB's construction equipment strength is in wheeled and backhoe machines — its wheel loaders and backhoe loaders push and move material, but neither is engineered as a track-drive dozer for grading and heavy pushing work. If you need genuine crawler dozer hydraulics, several brands on this site currently manufacture real bulldozers.