I don't think the 1983 W126(280SEL) was sold in the USA.
My parts place said if you could get the engine no. he might be able to help you. Better yet, would be to get the no. from your defective unit. You could then call your dealer in Singapore and get the part. A similar unit in the USA costs $210.00. Good luck....
Bill Lewallen Lexington,Ky.