What, if any, are the differences between these two? Looking on the Apple site it appears that Player 7 is for later - i.e. up to 10.6.3 - versions of OS X while earlier versions stop at Leopard. I am perhaps confused by the change in title.
I have QT 7.6.6 here (on Sierra). QT 7 is the 'old' version of QT compared to the current QT Player 10.4. It supports some extra (older) video formats and (if you purchased a 'Pro' key) some useful editing features.
I suspect that QT 7 and QT Player 7 are the same thing so you are just looking at QT 7.6.4 as a particular version of the generic QT 7. This Apple support page seems to support that view by using both terms for the same thing.
Michael Corgan 