The more normal Boot replacment is to use a Flexx Boot or the Similar Dorman Product (the Factory Style of Boots are too thick to be stretched) and stretch it over the what I call Can on the Axle.
The other issue is that the Joints came from the factory filled with Oil not grease.
When replacing the Boots some insist on haveing Oil others are OK with Grease.
A split Boot is not the best choice to use Oil with.
A few years ago there was a Seller on eBay that sold split Boots. I ask him if any were made to fit Mercedes and he checked his Supplier and the answer was no.
He said if I had any dimensions to give Him he would see if there was something close. I did not have dimensions so that sort of ended his helping me.
You might look here for rebooting info:
Repair Links DIY Links by Parts Category - PeachParts Mercedes ShopForum
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