Years ago I installed lowering springs on my first car and was concerned with the struts as well. I contacted Monroe and they gave me a part listing for struts intended for my car when lowered in the Sensa-Trac line. It was a different part number from the stock ride height strut. The car was a 1988 Escort EXP. If they made lowering struts for that car I would imagine they made them for quite a few others as well. The price was the same as for the stock Sensa-Trac struts. Unfortunately they didn't seem to advertise that they had such a beast so it wouldn't surprise me if the line didn't sell well and they have since discontinued it. Seems like it would be worth a call to their Customer Support line.
-Rod