Lost key

I have lost the only key I have to my 1984 500SEL Grey Market.

Locksmiths want $200 to make a key because It is a sidewinder key.
What exactly are my options here.

The locksmith tells me that I can get another key from the dealer for
about $40 and they should get it overnight. I heard your screwed if
you have a grey market car though.

Changing the lock cylinder seems impossible from what I have read on
the group unless you can turn the key to the 1 position, which I cant
do since I have no other keys. What would be my best shot here. Any
help would be so greatly appreciated.Thanks

master key available at mercedes dealer online $9.oo