need Postscript for old Gestetner printer. Who can supply?

I assume you are asking for a source of upgrading a Gestetner printer to interpret PostScript as well as whatever other page description language the particular printer supports.

Gestetner was purchased by Ricoh in 1995 and was consolidated with Ricoh's Lanier division in 2007.

Any printer that is branded as Gestetner is probably quite old, but you may have luck checking on support for such a device (as well as availability of a PostScript option) by contacting Lanier.  Copiers, Printers, and Document Solutions from Lanier.

        - Dov

Moving this discussion to the Adobe PostScript forum.