Hmm
As far I know, no Mega Station is found here. Or elsewhere.
I guess, [HW2]T.E.O.T. mod had some cyclopic models (I might be wrong), but You must talk to them.
Of [HW2]Sands of Time got some mega-models, but I doubt they want to give them to smbd.
You should consider doing it yourself
) The only chance
Btw, why do you need it, if it`s not a secret?