The adapter is custom made by TMG performance of Greece...
They do 2 versions of the adapter - the bit cheaper thinner one that leaves a gap between the adapter and the head, and the full one as pictured above.
Just the adapter:
http://www.tmg-performance.com/en/axesouar-veltiosis/alla/r8-285.html
The adapter with coils package:
http://www.tmg-performance.com/en/axesouar-veltiosis/alla/r8-314.html
They do 2 versions of the adapter - the bit cheaper thinner one that leaves a gap between the adapter and the head, and the full one as pictured above.
Just the adapter:
http://www.tmg-performance.com/en/axesouar-veltiosis/alla/r8-285.html
The adapter with coils package:
http://www.tmg-performance.com/en/axesouar-veltiosis/alla/r8-314.html