An excellent write up on the Silver Socket appears on Richard Atwell's site:
http://www.ratwell.com/technical/SilverSocket.html

Steve Lashley from EuroCampers offers them and plugs on his site:
http://secure.mycart.net/catalogs/catalog.asp?prodid=1105726

The Trim Shop (which specializes in selling stuff for type 181 VW Things)
has a herd of accessories which plug in to this socket. They're located in
Phoenix, Arizona, and their phone number is 800.966.7791.
(This paragragh quoted from Vanagon.com - dunno if the phone number is still
valid)
http://www.vanagon.com/info/faq/#silver_socket

Check these links out for more info

Enjoy....
--
Jim Thompson
84 Westfalia 2.1 "Ole Putt"
73 K Ghia Coupe "Denise"
72 411 Station Wagon "Pug"
oldvolkshome@gmail.com
http://www.oldvolkshome.com
**********************************
On 2/7/06, dylan friedman <insyncro@yahoo.com> wrote:
>
> Jim,
> Thank you for sharring!!  One of my 91 Syncros has it.  I even pulled the
> dash to see if it was stock.  Sure looks to be.  I haven't used it though.
> Where can I pick up an accessory to test it?  TIA.
>
> dylan
>
> *Old Volks Home <oldvolkshome@GMAIL.COM>* wrote:
>
> Aaron -
>
> This is a subject that comes up perennially for as long as the Vanagon
> List
> has existed.
>
> The Silver Socket is a Power Outlet that is normally installed on
> Westfalias
> (standard) and I've seen them on some MultiVans and Weekenders. It made
> it's appearance in the late 70s on the Bay Window Westfalia. It normally
> resides on the portion of Dash Face near the Cig Lighter. It looks like a
> Silver disc with a hole in the center where the power cord for your
> particular accessory. Being European by design, it can be assumed that
> mostly European made (and European sold) 12 volt Accessories are plugged
> into it. There were a few VAG/VOA Accessories available for it's use at
> one
> time.
>
> In addition to John Deere Tractors, they were also found on VW Type 181
> Things and BMW Motorcycles. The Trim Shop (aka The Thing Shop) in Arizona,
> BMW Motorcycle Dealers and I guess John Deere distributors carry the
> socket
> as well as the plug for this receptacle. I've rewired a number of cig
> plugs
> with this plug to utlize my Silver Socket over the years. IMHO I think
> it's
> a better connector to use than the cig lighter socket.
>
> Hi-Yo Silver Socket! :-)
> --
> Jim Thompson
> 84 Westfalia 2.1 "Ole Putt"
> 73 K Ghia Coupe "Denise"
> 72 411 Station Wagon "Pug"
> oldvolkshome@gmail.com
> http://www.oldvolkshome.com
> **********************************
> On 2/7/06, Aaron Pearson wrote:
> >
> > okay, what is a silver socket? i remember this came up once before in a
> > list of quirky vanagon features, but no one ever said where it is or
> what
> > it
> > does. do they all have one? my new van plays the song on start up, i
> > didn't know what everyone was talking about until last weekend when i
> > drove
> > it for the first time. my old van was silent. where's the silver
> > socket???
> >
> > aaron
> > '87 syncro westy ej22
> >
> >
> > >From: Old Volks Home
> > >Reply-To: Old Volks Home
> > >To: vanagon@GERRY.VANAGON.COM
> > >Subject: Re: Silver socket for your John Deere.
> > >Date: Tue, 7 Feb 2006 14:35:13 -0800
> > >
> > >And the Silver Socket Rides Again! (Lone Ranger music fading in the
> > >background)
> > >--
> > >Jim Thompson
> > >84 Westfalia 2.1 "Ole Putt"
> > >73 K Ghia Coupe "Denise"
> > >72 411 Station Wagon "Pug"
> > >oldvolkshome@gmail.com
> > >http://www.oldvolkshome.com
> > >**********************************
> > >On 2/7/06, Pensioner wrote:
> > > >
> > > > These fit the 'silver socket'
> > > >
> > > > Prices are not current or voltage for that matter...
> > > >
> > > > Left side:
> > > > John Deere SOCKET OUTLET,
> > > > Part Number: AL25073,
> > > > Cost: $6.35
> > > >
> > > > Right Side:
> > > > John Deere PLUG,
> > > > Part Number: RE11344,
> > > > Cost: $8.32
> > > >
> > > > Yet another electrifying experience...
> > > >
> > > > p
>
>