Gemini GTA-8 Mission USS Boxer Cover Discussion
 

The first cover shown below is very interesting.  It has a GREEN printed cachet with a "clear" background.  It is certain that Beck did not print this cachet.  The cancellation is the hand cancel and is discussed on page 23 in Ray E. Cartier's book Primary Recovery Ship Cover Handbook, 1993, 1998.  In his book, Cartier shows a similar thermo graphed cachet and states that the cachet shown is of unknown origin.  He further states that the hand cancel is scarce. 

The specific cover shown below is very interesting because it is addressed to CDR Tilton, HS-5 (Helicopter Anti-submarine Squadron Five).   In our opinion, this clearly indicates that this cover is genuine and was indeed postmarked on the Boxer.  We believe that this is a CREW cover printed on board the ship.

The following "CREW" covers were offered on eBay in 2006 by Space Dealer Karl Hass.
Note that these covers are addressed to members of the crew. 
In our opinion, these are genuine covers that were aboard the Boxer. 
These covers also have the hand cancel which is seen less often than the machine cancel.
Note that the hand cancel shown on these covers has not been observed on a Beck printed cachet with or without the cachet number.

Scan of gold cachet courtesy of Karl Hass

Scan of gold cachet courtesy of Karl Hass

Scan of gold cachet courtesy of Karl Hass

Scan of gold cachet courtesy of Dr. Ross J. Smith

Scan of red cachet courtesy of Karl Hass