I figured that it was a bit of a 'leg pull' ;o))

 

I didn't! nothing stuns me anymore with some of the 'fixes' I've seen over the years.

A second hand door seal would be the answer for me, it's a time consumer to fit but once it's on the door shuts and the seal is there, you can even feel pressure difference in the ears!

 

Well, it certainly isn't perfect, but a bit better than the backer rod. The car I bought is lovely, but far from show winner. I have bigger fish to fry than this seal.
This works very well. The road noise has been all but eliminated.
The seal came with adhesive, plus I added some 3M weatherstripping adhesive that I had from a different job. I also reused the stock, yellow clips. This strip will not be coming off accidentally.
I will go back and fill the small gaps with some black silicone, for looks really, and I will consider it done. You can only see it when the passenger door is open, and frankly you probably wouldn't notice right away. Of course in the picture it will be totally obvious.

 

I saved this pic and lightened it up a bit to have a good look at it and guess what, I would consider that to be perfectly OK ;o))
Just a few dabs of black silicone as you say and place a strip of selotape...sticky tape over the joins until it cures and it will look like it grew there to the casual obsrever.
Of course, us experts here who are judgemental know different ;o)=)