Myself being a genius, I had misplaced the original set of keys for my baby blue 250sl.
I know they are somewhere in my home and hope to locate some day.
Luckily about 20 years ago I made copies of the ignition and trunk keys ( to safeguard the originals ! ) and that's what I have been using.
I saw a mention of replacement keys on here - via the Classic Center using the key numbers on my data card.
So I contacted them , was asked to send a copy of the data card and sure enough I just received the 3 keys for a mere $ 55. US plus shipping.
The 2 small keys seem to be cut on the original , all metal " Ymos " key blanks. The larger ignition key unfortunately came with the later rubber top.
It's pouring rain here in NJ, so I can't venture out to my remote garage to test them, but will tomorrow.
I was wondering how the keys are cut. Do you think that my key numbers are fed into a computer that produces an "original" cut key, or do you think it is cut using another key to make a " copy " like you get at the hardware store ?
Anyway, I thought it was a bargain and pass it on.
jz