At Mercedes dealer, they are available, cost pennies. While at it, you may want to get the seals for type designation as well. It is quite important to seal it well or otherwise you would be puzzled where has this water in the trunk come from? Similarly with type designations.
PN for type designation seals A 115 987 03 41, may be with 64 added at the end. Do not remember how many you need... they are available as well. For this you may also need locks A 000 994 27 45.
You can also easily fabricate the seals - a couple of hole punches and a piece of rubber.