can the sending unit for the vdo head temp gage be bought seperate and for how much?

try,

http://www.egauges.com/vdo_send.asp?Sender...=Cyl_Head&Cart=

which one

Aircooled.net has exactly the one you require for something like $15. The spark plug ring version.

Is this the sending unit for the VDO center consol temp guage?
I have the gauge but have not yet hooked it up because.....I don't have a sending unit.

Unless I misunderstood, this is for an aftermarket VDO cylinder head temp gauge. The console gauge is oil temp. Different sender. If you want an oil temp gauge for the console, a gauge/sender combo can be had for roughly $60. The standard VDO oil temp sender may even be compatible with the console gauge you already have.