I would say go with a Spoon Engine Assy. Spoon B16 and B18 cost the same. They are 11.3:1 Compresion. It is only the Center Mass but you can add any B-Series parts to it (Type-R Exh. Manifold). I have seen this Engine go for $6000 on other web-sites but,
www.automotiveforums.com has it for $3500. I called and they are still adding Spoon parts.
Nice web-site also!!
Peace
Drew
www.automotiveforums.com