Have just ordered a set of 619 18" 7 series wheels from German ebay. They are available from about £750 with as-new tyres and latest RDCi. The 619 wheel will fit fine: it's the standard SE wheel for higher powered G30s, though the tyre size is different (245/50 on G11, 245/45 on G30).
(I'm currently running non-RFTs on some F10 236 18" wheels so I'll do a tyre swap and sell on the 236 wheels to a UK 7 or 5GT owner).
619 alloys are boring looking but very light. Forged, not cast:
http://www.bmw.co.uk/en_GB/topics/di...yId=11274.html
Made by Fuchs:
http://www.fuchsfelge.de/index.php?id=1105&L=1