Fujitsu makes industrial/business grade products, they have some of the best build quality of any manufacture so you pay for that. Fujitsu and cheap do not go together at all. I have know two people that owned convertible tablets from Fujitsu and their build quality could not be touched by any other manufacture.
I honestly dont know, there are unboxing videos on youtube that could answer that question, but I am currently unable to access those video to double check. It lists it as optional in a lot of places, but i don't see sold separately anywhere. If anyone knows for sure please chime in.
I don't think it includes the keyboard. You can purchase it on Fujitsu's website for $389.00
Click on Docking and Mounts
after clicking on the link.