2011 Audi S6 Radiator upgrade?

My C6 S6 has a radiator that is leaking. Are there ANY upgrades currently in open market? I saw a CSF but it was not fully aluminum. Would OEM be the safest bet? I need to order ASAP

Me and my father got a csf one but it didn’t have the port for the antifreeze that goes into the aux radiator. So we made one and so far it seems to be working but i don’t know of any other radiators as in aftermarket that’ll come with the port leading into the aux