OK, I have to ask, have you pulled out a globe and looked at it, and looked at where Florida is, and looked at where Moscow is? I ask, because Moscow is much closer going the other way, and trust me, much less of a hassle.
I'm friends with some folks who have flown to Russia from Alaska. It's an incredible paperwork nightmare. You get permission for a single day and time. if you don't make that, you reapply for another slot. You fly a designated route at a designated time. You have to report certain positions within certain times or problems result. There is no Avgas. The folks I know ship drums of avgas to Proividenya ahead of time. The Alaska Airman's Association is probably your best source of information. They will likely seem engouraging, but you should be aware that they have been tilting at this particular windmill with summer trips for 15 years, and as far as I know they haven't yet made as far a Anadyr. Look up Providenya and Anadyr on a chart. Now look how much further Moscow is. Getting to Providenya, while a monumental hassle, will be the easy part. they are used to the yearly tours from the crazy Alaskans. there are folks who are willing to store the fuel for them rather than sell it on the Black Market. The customs and aviation officials are used to dealing with them. Once you're beyond Anadyr, none of this will be true. You'll be flying across some of the most desolate terrain you could ever imagine. Makes Alaska seem positively suburban. Facilities, fuel, Maintenance will be non-existent. I don't mean non-existent as in "hard to find", I mean non-existent as in "they don't exist", no matter how hard you look. I don't know what sort of range 466 gallons will give you, but unless it will take you comfortably from Nome to Moscow wihout refuelling, your fuel logistics will be a *very* serious and uncertain understaking.
If I had an airplane here in Anchorage which I needed to fly to Moscow, I'd give some very serious though to flying East. (approximately same distance, significantly less hassle) If I were in Florida, it would be a no-brainer. Going East you have civilization, you have countries that actually have private civil aviation, so will have fuel, services, etc, readily available at least as far east as Germany, after that, it will get increasingly more difficult, but from Germany, Moscow would be a fairly comfortable, if long flight on the airways
