If it is a C class then the refill is still available at the dealer. Many were discontinued but not this one. At least the one for my car. There is another thread about this. I think they are about 10.00. I can post the PN but it is in the other thread.

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra