abdullah412, I did a quick check on the part number and availability through Mercedes dealers.
The number provided, A 1270721401 as well as another part number for this bearing holder, A 1270701724, are correct, but not valid anymore in Mercedes system, so the dealer may not be able to find them and will tell you they do not have them. I think what you need and can get is part number A1300700224. In my geography it is 72hours availability and it costs net (no VAT) about $100.
But if you order through Mercedes, please double check it with the dealer if it is suitable for your engine number. Tell the dealer to look for it in the EPC under Injection Pump section. I bet you they will look for it in engine housing, but they will not find it there
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