Oh, I didn’t know that all that scripting information was available at the Inside Omnifocus part of Omni’s website! I thought that Inside Omnifocus only contained interviews with different types of users. Great information!
Dan Byler’s scripts didn’t look exactly like the script I was looking for. From what I could see, the scripts had dialogs, and they also contained Growl parts which I would prefer not having, even if they might not matter at all. But there was also a very humble link to some Helmut:
Helmut Hauser: Speed deferring Omnifocus tasks
And he on his part linked to a script from C-Command:
There it was - exactly the script I was looking for! The only thing I had to do was to change a digit in the script to the number of days I would like to have my tasks deferred.
Thanks for showing the way, @ediventurin!