We just bought a ticket the other way, Moscow to Dallas and back, for 1/1/23-1/12/23. We spent a little more to buy more convenient flights with shorter layovers, but we could have bought the ticket for $1700-1900, with longer layovers.
For Dallas - Moscow trips, it is cheapest through Istanbul, based on our experience. You can normally find a good deal to get to and from Istanbul, but getting from Istanbul to Moscow can cost more than Dallas to Istanbul, depending on the flight chosen. When I traveled to Moscow back in July, I bought Turkish Air flights to IST and back and then Azerbaijan Air through Baku for the IST-Moscow part.
Like someone else mentioned, try buying the 2 legs (US-Turkey and Turkey-Russia) separately. If you do that, you'll have to clear customs in Istanbul, but it could save you several hundred dollars.
Good luck. There are alternatives out there.