They did come as a wagon, but Europe and Japland only, to my knowledge.
The Euro/OZ versions all came out with the first incarnation of VG30E. In Japland they were available with both the VG20ET, VG30E, VG30ET, RD28 diesel. They were not available with the VG30DET or VG30DETT. The Y31 was available with these later VG30DET variants.
OZ spec were all automatics, were as the Euro wagon, AKA The Estate, came as a 5 speed stick shift. Japland models seem to be less structured, with the manuals seeming to be an option on most models. The Estate also came as a 8 seater column shifter.
If you're interested check this site out.
300c Owners Club