Sue,The R stands for right handed trip lever placement, so the CST744EG#01 has a trip lever on the left hand side, while the CST744ERG#01 has it on the right hand side. Let us know if we can assist you with anything else.
This unit would not include the seat and cover as we would suggest SS114
Toto toilets are made all over the world so we can't say exactly where the toilet components you receive will come from. They have a plant in GA but a great deal of their products are imported.
For the 10 inch version, it's CST744EF.10#01. You have to sacrifice Sanagloss though to get that model.