psnup from psutils should do what you want.
psmerge figure[0-9].eps | psnup -4 | lpr
From the Description field in the Debian packaged version:
Description-en: PostScript document handling utilities
This collection of utilities is for manipulating PostScript documents. Page selection and rearrangement are supported, including arrangement into signatures for booklet printing, and page merging for n-up printing.
The following programs are included in psutils: epsffit, extractres, fixdlsrps, fixfmps, fixmacps, fixpsditps, fixpspps, fixscribeps, fixtpps, fixwfwps, fixwpps, fixwwps, getafm, includeres, psbook, psmerge, psnup, psresize, psselect, pstops, showchar