oh... ok.
I dont think it should be locked on the end game, instead, I would suggest something more realistic.
Space has no gravity, you dont need much "fixed" structure to dock a spaceship, but on the ground, you have lots of gravity and space is limited, instead of locking in later research, you could make the docking station very expensive, first because it needs to hold a gigantic spaceship that weights literal tons, you can even use bulk inserters as ingredients because you need to "grab" the spaceship, and the second reason is to delimit the place you can build/land the spaceship.
I would use tiles, just like the spaceship floor, to create the same "orbit space", but with a texture of inserters and/or scaffolding.
For the recipe:
4 refined concrete
1 bulk inserter
2 electric engine
10 steel
= 4 (or less) land spaceship dock
Just a suggestion
My direction focuses more on being expensive and hard as you make things bigger instead of a simple ultra expensive late game unlock and free access after, your first spaceship can be small, enough to make you leave to space, a small dock is enough, want to make a big cargo ship? be ready to use shit tons of resources building a a giant dock.