Your wrong sir. USDM b18c engine is actually B18c1 aka GSR engine AKA UKDM B18c4 engine. You can buy pistons for any motor in America, not just b18c5.
Hi Blinx
I spoke to toda in australia, they told me if your not sure about the pistons, just get a thick head gasket to lower the comp..
So i asked the company in america, Race Engineering, Inc .. see below what they said..
Product is : MLS GASKET:B16A/B18C-81mm/120" (EA)
SKU: CM-C4231-120
Weight: 3.00
Price: $193.45
((The gasket will fit the B18C5 but i do not have information on the B18C7 so i can not guarentee the gasket will be proper.
It would take a .120" (3mm) thick gasket to lower your compression by 2 points. Cost would be $193.45 plus shipping.))
I checked on wikipedia and a whole lot of forums, it all points to same thing, that there is no internal engine difference between the B18C5 and B18C7 ..
What do you think ?