Engine won't start!

Hello,
My car details: Passat 3B, year of manufacture 6/2000, TDI, 90 hp, MKB: Bosch distributor injection pump, approximately 200,000 km
This problem has developed over a longer period of time.
Whenever I park my car crookedly (it's happened twice so far, the passenger side was hanging down), my car no longer starts properly. The ADAC (German emergency call service) always towed me, and after about 200 meters, it would start and run normally again. However, on a straight surface, it always started well. Last week, however, the starting process deteriorated significantly, so that it no longer starts even on a straight surface. Dragging it around also doesn't help anymore.
During the initial troubleshooting, I discovered that when starting the engine from the ESP (connected to the fuel lines in the lower rear portion), it was either dripping or even running.
The car has been running normally so far. There has been no loss of power or anything like that. Should I expect my fuel pump to have failed, or is it just a faulty seal? Has anyone of you experienced something similar before?

Does it run directly at the fitting?
If so, check the fuel lines for proper seating.
If they are firm, check for hair cracks.

This can happen if, after a timing belt replacement, the starting point is dynamically set and then the lines are not subsequently loosened (resulting in tension/vibration cracks).

If it's not the wires, then the ESP is probably dead.

The fuel lines are in good condition. There is everything tight and firm.
The diesel is leaking at the rear part. Somewhere on the lower part, which I can't see. Tomorrow, the pump will be removed, and then I'll assess the situation.
Do you know any affordable pump replacement options besides Bosch?
What costs will I have to bear?

Hi!

So, wenn die Pumpe undicht ist, kostet die Reparatur nach meiner Erfahrung beim Bosch-Service etwa 300 - 350 €. Dafür werden aber alle Dichtungen neu ersetzt.

But there are also negative experiences, two out of two injection pumps I had from Bosch, came back incorrectly adjusted, so that the starting amount was much too low

Best regards, Christian