I dont know about the steel crank but I have been told that all honda pistons are cast not forged. Maybe the JDM Type R's have forged but I dont know. I have a JDM b16a SiRII in my Civic and you can buy parts for a 99-00 Civic Si, 94-01 Integra DOHC VTEC, or a 97 del Sol DOHC VTEC. So far I have radiator hoses from a 99-00 Si and a rad from an EG6 in Japan and also axle nuts from a 99-00 Si. I used a kit that reseals the fuel injectors from a 97 del Sol. Hope this helps you out in finding parts you need.
A quick word about radiator hoses: buy them from Honda. You can tell them what motor you have and what the USDM equivalent is and they can get it for you. I ended up buying and returning 4 radiator hoses from AutoZone, Advance Auto Parts and O'Reilly's Auto before I said "Screw it. Im calling Honda!" Save yourself the hassle and spend a couple more bucks and do it right the first time. Cheers!!