A couple of liberties taken, though. I don't think that space tug or space station (adjacent to the Romulan and Klingon vessels) were ever in TOS...
The tug is from the remastered episodes ("Charlie X" to be precise):
The design was based on the grain carrier from the animated episode "More Tribbles More Troubles".
The space station is based on a Starfleet Command Headquarters design by Franz Joseph: