Repair my High Pressure Fuel Pump?
 

My high pressure fuel pump is going out and I'm recently unemployed... I found this video on YouTube that gives a couple of potential causes and "hail marys" LOL
I would be willing to give it a shot since the new pump is $700 after taxes since I have another vehicle to drive.
This video concentrates on the metal bellows and the oil inside on the drive (not fuel) side of the pump.
The solenoid is also discussed briefly... but not a lot. Anybody have advice? I've got nothing to loose!

My Oil Reservoir Measurements
 

I was able to get an approximate measurement of the oil reservoir diaphragm position by sticking a paper clip gently up into the hole and mark it with a Sharpie. After that I took it out and measured from the mark to the end of the clip - 28mm is what I got so according to the video there is reasonable cause to believe the amount of hydraulic oil inside is a likely suspect. This of course begs the question "where did the oil go?" The solution offered appears to be put thicker oil back in - any thoughts on that?