In a message dated 9/29/2013 6:03:57 P.M. Eastern Daylight Time,
jim.felder@GMAIL.COM writes:

Has  someone ever tried to install headrests on the rear seat of  the
>>> vanagons? And if yes, where to buy those kits?  Thanks
>>>

IIRC GoWesty or JustKampers has these kits for  sale..