Well, this is the best public Russian space forum. Won't get any better in Russian, with all Russian sources.
So - yes, I agree that the information sources are limited. But at least you can try to trace the original sources from posts there.
On the original question, I haven't seen a comparison of actual SpaceX launch prices with actual launch prices used by other launch providers, specifically Russian ones. With Russians it could be useful to check both "commercial" and "federal" launch prices, as the first are driven by market, while second are more driven by actual costs.