I found out that Hy-Gain sells the base element separately! Maybe many other people have been having the same problem as me. Anyway, I ordered one right away via Norad for something like 70 Euros.
I have now gone through the antenna to check what condition it is in. The bottom section is very bad and there are lots of things to be done before this antenna can do me any good.
It is spring, the sun is shining in Denmark and I am on vacation. It’s time to clean the DX-88 and put it up.