If it’s all part of the same repeater, maybe.
you can create an acf/load_value filter on the repeater field http://www.advancedcustomfields.com/resources/acfload_value/
In this filter you it would be possible to remove duplicate values. The value for the repeater will be a multidimensional array that looks something like this:
$value = array( // there will be a nested array for each row array( // each field in the row will have a value 'type' => 'website', 'value' => 'http://www.website.com/' ) )
You could loop through the array, record what’s in each row and delete the duplicates, you could also get the value of another field to check to see it that is duplicated as well. At least in theory this might do what you need.
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