Go to showmetheparts to cross reference the part. ShowMeTheParts Catalog

Description:
V-Power Plug, 14mm Thread Size, 26.5mm (1.04") Reach, 5/8" (16mm) Hex Size, Gasket Seat, Resistor, Projected Tip, Solid Terminal Nut, V-Power (V-Grooved Center Electrode), .043" (1.1mm) Gap, Heat Range 5

To purchase:
http://www.ngk.com/results_cross.asp?pid=LFR5A-11

or here...
http://autoparts.greencarreports.com/auto-part/ngk-6376--ngk-6376-lfr5a-11-v-power-spark-plug-pack-of-1

cross to a Denso;..
http://autoparts.greencarreports.com/auto-part/denso-5343--denso-5343-ikh16-iridium-spark-plug-pack-of-1
or
http://autoparts.greencarreports.com/auto-part/denso-3417--denso-3417-sk16hr11-iridium-long-life-spark-plug-pack-of-1
or just a standard NGK #...
http://autoparts.greencarreports.com/auto-part/ngk-5018--ngk-5018-spark-plug
And last but not least:...