Originally Posted by ChassisInnovations
If you don't have a huge budget, JDM ITR pistons (P73-00) or USDM B16A pistons (PR3) raise compression to around 11.3:1 when using a OEM head gasket. This is a good compression ratio if you daily drive your car and don't want to use higher than 91 octane.
Of course, you will need a lot of other mods (valvetrain, tuning, exhaust, etc) to make full use of the higher compression ratio.
werd plus you can get brand new type-r pistons for about 170... though i wont say where because you as a vendor might want to suggest your own alternative