Shock Absorber Recommendation for '82 240D (W123)?

[lpozzo]

I have a 1982 240D that I would like to replace all 4 shock absorbers. I am interested in replacing them with Bilstein shocks and there seems to be Heavy Duty or Comfort-Heavy Duty. What is the difference between the various Bilstein shocks?

Also, does the 240D have self-leveling suspension? Any other brands that you would recommend to replace the shocks? Thanks for your help.