Answer
Yes. Several ARCINFO plotting commands, such as HPGL2, COLORHCBS and POSTSCRIPT, enable an increase or decrease of output size when processing an existing map metafile. The ARCPLOT command PLOT can also be used with the BOX option to create another metafile.
Note that increasing or decreasing the size of the map may cause information on the map to be inaccurate, such as scale information.