What is special about Viewmaster reel #1305?

PRESIDENT KENNEDY VISITS IRELAND June 1963
Single reel #1305 issued in USA in October, 1963 then pulled from distribution following assassination. The reel was reportedly marketed in Europe.

http://www.rollanet.org/~vbeydler/van/vmcolect.htm

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Perhaps the most collectable of all reels is View-Master No:1305 entitled President Kennedy's Visit to Ireland from 1963.Quickly withdrawn for sale after JFK was assassinated, this item has sold for more than $400 in America.

http://reviews.ebay.com.au/View-Master-The-Reel-Story_W0QQugidZ10000000001190726

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