The MB dealer. Do not let them tell you "the car is too old, we do not have it".
They will not have not tinted, I suppose, it is not available, tinted is.
They have to go to subgroup "Heat Absorbing glass" and switch off the filters. Then you will have the PN starting with 113 for your windscreen. Could be GBP 800 or so.
You may need the rubber frame ornamental inserts as well, A 113 671 01 30 and A 113 671 02 30, if you cannot recover yours - but these you may look for outside of MB, they are expensive there. The 2 connecting clips for them are A 110 678 04 37. Rubber frame is A 113 671 02 20, I think best is to buy rubber from Mercedes.