Would it make you feel better if he paid for it? It’s healthy for a functioning democracy to leverage foreign intelligence assets with the intent of finding dirt. I am sure there is a cell somewhere searching for Mayor Pete’s elementary school essays.
Paid for what? It's not like it's legal to buy hacked emails & their timely release. It might actually be legal to pay for the services of the kind of troll army effort the IRA put out for Trump but then there would be an unseemly money trail.
OTOH, it would be perfectly legal for the RNC, for example, to hire a law firm to hire a research firm to hire an individual of any nationality to do research, so long as they pay fair market value. You'll notice that the FEC didn't complain a bit when the DNC did just that. They didn't complain when the GOP availed themselves of the services of Cambridge Analytica, either.