I noticed this yesterday when i was looking for a coolant leak. Is there just a seal that goes in between?

 

That appears to be the brake hydro-boost unit leaking. I don't believe it's a seal that's easy to replace, more likely replace the hydro-boost unit if it gets worse. That's power steering fluid used to power the hydro-boost, so keep an eye on the PS fluid level so you don't run out.