Diesel injection pump isn't really suitable, the clearances inside required to get up to 115 bar to 280 bar - 1700 psi to 4,000 psi means the slightest lack of lubrication or grit and it's toast.

Going slightly off topic but whilst looking up these pressures which I had forgotten [ past life ] I found out that the latest diesel with high pressure common rail systems use pressures up to 2,000 Bar or 29,400 psi.

Home made water jet anyone ?