...and are multilingual in profanity like I am....
Here's the update almost 6 years later- The left driver's side # 551 is available from the BMW dealer for $30.11. It is gray-colored rubber that is slightly lubricated in the plastic bag. I found out my car didn't have either gasket when it was judged at LOTA in Hilton Head last November. I was told they were "readily available". So I bought both of them. I struggled squeezing on the 551 on the left side. The 552 right side was black and not lubricated. It did not want to slide into place like on the left side. Turns out, the 552 is really a left side 551 in the wrong plastic bag with the correct part # on the bag. The dealer then ordered 2 more of the 552 parts for me. They came from a BMW warehouse in California,the only BMW source here in the US. Both of the plastic bags marked 552 had the left 551 in them. It is safe to sat that anyone who orders the 551 and 552 gaskets from BMW will get 2 of the left 551 gaskets. The dealer told me BMW will not get any more from Germany until the stock in the California warehouse is depleted. Here are pics of the wrong part 552 bags and the 551 installed on my car with the 552 wrong part laying next to the installed 551. You can see all of them are the same gasket.Alan,
Both right and left sides are available for about $15.00 each.
51711802551
51711802552
Oh and they are a PITA to install unless you use some sort of assembly lube and are multilingual in profanity like I am.