Yes, can you explain, in words, how it should go. I see you have unsorted, and you want the characters on the output in order. Also duplicates dropped?
Do you have a maximum of three pairs of non-duplicate characters?
Why are you using PARSE considering that the fields are in fixed positions?
PARSE is used when the fields are delimited with different lengths. Your PARSEd fields are equivalent to 1,2 and 3,7 - you don't need PARSE. Other than that, I don't know if your solution is a good one considering that the OP has not really explained what he wants to do.
As Bill indicated, you need to do a better job of explaining the rules for what you want to do. It's certainly not clear from your example.