I would be looking for a 95 E300D It has an aspirated 6 cylinder diesel, non-turbo. This is the last of the 124 model MB cars, same body as your 300E but with remodeled grill and lights. These cars deliver great fuel economy and will very likely go 400K to 500K with proper maint. You may expect to pay anywhere from $8,000 to $14,000 with lower mileage.