OK. This is all in my opinion only.. so take it with a grain of salt.
Engine oil, 5W-40, is FINE for your 2.7 Liter Engine in that car. If you change your oil every 3000-5000 Miles, (umm... 4000-7000 KM's ? I think?) then using 5W40 will not harm your engine at all. Any brand oil will work, provided it is of good quality. Fully Synthetic oil would be the best to use, as it will handle your cold Moscow winters MUCH better than regular oil.
For your Differential, I would just get the standard 75W-90 Gear lube that is used in regular Rear Wheel Drive cars. The brand really isn't as important here either.
One thing that i WOULD stress, is that you find a source of Mopar brand ATF+4 Transmission fluid. I am not sure how easy that is to find there, but you might be able to purchase it from a Chrysler or Jeep center if dodge isn't sold over there. Otherwise I would looking into having it shipped to you somehow. These transmissions work well, if you take care of them. make SURE you can get some Mopar ATF +4 fluid in there. (ATF +3 would work, but the +4 is better)