the 280ZX (1979-1983) is a different animal alltogether, the 280Z (1975-1778) however yes you can swap the skinny 240Z bumpers on, the driving lights grill and valance are different as well but the bumpers are the most noticiable parts
here is a turbo 280ZX on beay in FL right now,
http://cgi.ebay.com/ebaymotors...wItem you might want to keep an eye on the classifieds on zcar.com, hybridz.org, and any number of other z car sites