Trouble locating this fuel valve - 220d 1973

[jordan220d]

Hello all,
I recently acquired a 220d 1973. It runs great but is having trouble starting. I've replaced all the fuel lines, new glow plugs, checked compression, new diaphragm on the injection pump, and still having trouble starting. My mechanic and I both agree that the fuel pump valves (where the hand primer pump) are worn out and need to be replaced. I've been on the hunt for 3 weeks trying to track down the correct valves. I've done two orders for these valves from the internet and both times, the valves I am getting (which say they are for the 220d 69-73) is not the correct size. They are slightly too big and do not fit into the hole. I need to locate the correct, smaller fuel valves. Does anyone know where I might be able to find these online? I have seen some sources for $25-$30 which are non-refundable. I don't want to keep spending non-refundable cash on these parts to try and locate.

Here is the part I recently ordered, but it does not fit:
https://www.amazon.com/gp/product/B001G5WWJA/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I found this thread, but not sure if its the same part:
http://www.peachparts.com/shopforum/vintage-mercedes/368673-w115-220d-240d-lift-pump-valve-rebuild-kit.html

I have attached a photo of the original valve and the replacement valve, which is slightly too big.

PHOTO OF OLD VALVE AND NEW VALVE
http://www.peachparts.com/shopforum/attachments/vintage-mercedes/138342d1473355327-w115-220d-240d-lift-pump-valve-rebuild-kit-image1.jpg



Thanks so much for all the info so far. I recently picked up this car 2 months ago and I have been going through making the engine run great. Once it's running like a sewing machine, I will clean it up and post some photos/videos here for you all to see it. I think I got a great deal - from the original owners son, I have the original owners certificate, a letter from Munich Germany to pick up the vehicle, mechanic book with documents and receipts and it just turned over on the mileage (not sure if its 100k or 200k miles). It's in great shape and I am really wanting to do everything right to make the car run as long as possible. This is my first diesel and my first mercedes (I am a long time air-cooled VW guy). Anyways, this place has been some of the best info to get my car running great and I appreciate the help and support here.

My best,
Jordan