Mark,
Does your 886F actually have the square ends on its original brush roll? If so, then you should go for the one that is square ended. The date code, as you said earlier, means your machine was made in January 1992.
Replacement brush roll: part no. 2675227000
Replacement belt: part no. 1044260001
Otherwise, if your brush roll has hex ends on it, a replacement should be part no. 2673273000 and a replacement belt to go with that is part no. 1672260001.
~Ben