Can anyone help "Are you paying too much for machinery maintainance"

Our company Gambetti UK ltd. has been contacted by various high profile golf course engineering departments after realising that Toro and John Deere are consistently charging in the order of 500% more for their spare parts fitted to there own manufacture sprayers then the same parts bought from Gambetti UK. These bigger clubs often running more then one sprayer realised that their Gambetti sprayer was fitted with some of the identical components, checking the prices from Gambetti UK they discovered to their horror what was happening. Has anyone else had a similar experience?. I know i have a vested interest in revealing this but smaller clubs are struggling and need help for the good of the industry.