wau, shipping 14 bikes to Magadan, this will not be easy but I think you can do it.
I did not ship this route, but I went in 2003 to Magadan overland.
As far as I know, there are no regular flights anymore between Alaska and Magadan, so you will have to charter an airplane that is big enough. I dont think I would ship a container to Magadan, I assume it will be a nightmare to get it thru customs (if it ever gets there), but maybe it is easy I dont know.
Maybe it is better to buy a 4x4 in Magadan and sell it in e.g. Ulan Ude before you enter Mongolia or after you have been to Mongolia.
Sorry this are just ideas, hope fully somebody that has shipped this route will answer as well.
Saludos de Bolivia