2001 Yamaha 150 HPDI TLRZ

[bald eagle44]

I am experiencing a problem with a momentary loss of RPM's on a 2001 VMax HPDI TLRZ. Usually this happens intermittenly at Higher RPM's around 4800-5200 RPMS, though I have had it happen on blast off and at 3700 RPMs. If I leave the throttle open the engine revs back up to rpms. This is only a momentary loss of RPM. I took it to a third Yamaha Dealer that tested it with me driving and we see that it lost fuel pressure momentarily. We checked electrical connections to ensure it wasn't in that area. Yamaha tells him they think it is a medium pressure pump in the VST that might be having intermittent issues. The pump is part number 68F-13907-00-00 and costs around $950 (Ouch).

1: Any experts thoughts would be very much appreciated

2: Any place I can get a used pump or a new one for cheaper?

Thanks

Bald Eagle