1983 Mercedes Benz 280sl starting problem

I have change almost everything on the car, even the gas tank. The engiine was running but idling very bad. The last thing that the mechanic let me order was a new fuel pump (the 3th one) new fuel distributor (also 3th one and the warm up regulator. After changing all those parts the car want start anymore. Now he want me tp buy new and not rebuit fuel distributor and new warm up regulator. Because those parts that I buy at Adsitco. In the US are junk. I dont trust this anymore because I don't think that a large Company as Adsit who sells only MB parts will let any rebuilder rebuild parts for them. I am a retired man and cannot spent so much on this car. Do you think that my case is an adjusting problem. Our problem is that here in Aruba even the MB agent has no capable mechanic who can solve this problem.