You're assuming N1c is original in Karelia because lots have it today. Autosomally Mesolithic Karelians are very different from modern ones, they aren't the same people. N1c is probably a recent arrival in northeast Europe. There was no obvious east Asian ancestry in both Mesolithic Russians, but modern Finno-Urgics heavy in N1c do have obvious east Asian ancestry.
Europe has gone through two major genetic events since the Mesolithic; arrival of west Asians during the Neolithic and migrations out of Russia during the bronze age. No region in Europe has had significant genetic continuum since the Mesolithic. Finno-Urgics are very similar to Indo European-speaking north Europeans, and can fit as being close to 50% Yamna. They aren't Mesolithic relics and have alot of recent common history with other northern Europeans.
Every Y DNA sample from pre-historic Russia-Siberia going all the way back to the Upper Palaeolithic is R, except for a few which are probably from foreign admixture. This is no coincidence.
If R1 came to Mesolithic Russia from west Asia, those west Asians had no ENF ancestry making them very different from modern west Asians. West Asia in this sense is just a geographic location. These R1-bearing west Asians would be as foreign to modern west Asians as Mesolithic Russians are.
Will you finally stop with your west Asian-centrism? No one is attacking west Asians. Saying most R1b and R1a in modern west Asians came from Europe isn't inferiorating west Asians. History doesn't follow agendas. It's the story of random events that were ignorant of each other(people had a little knowledge of history before modern times).
The slogan of historians should be "Random shit happened in the past".
I think there's alot of diversity of R1 and R in general in west and south Asia we should not ignore. If R1b1 was in Spain and Russia 7,000YBP, who's to say it wasn't in Siberia and Iraq. I don't agree with Davidski's simplistic ideas about R and ANE.