> The number of Vikings from Scandinavia who went to Rus, served in the near east, then returned to Scandinavia then invaded England (carrying their loot with them all the way) can’t have been many.

I really don't find this that unbelievable, especially when you consider that booty brought back from the Near East could be traded locally by Scandinavians. So it just takes one guy looting the Muslim world for the silver to make it to Scandinavia and then England.