Hi vanagonauts,
I met a guy last fall at the Jerome Jamboree in Arizona who makes these
and sells them for 10 dollars or less.  His name is Jim Harvey.  He
lives in Scottsdale AZ.  (602) 585-4745.  I bought one of his first
prototypes which could be removed while the door was open.  His newer
versions allow you to prop the door open and leave it open as no one
could open the door or remove the strut.  Give him a call, he was a nice
fellow.
Ken Wyatt
82 westy