I am not sure that I understand your question correctly, but here is what I think you are looking for.

;WITH CTE as (select row_number() OVER(partition by Binder_no ORDER BY Binder_id)

AS rn,office_id,Binder_id,Binder_no

FROM [Rev_Binders])

SELECT * FROM cte where rn = 1

Results:

rnoffice_idBinder_idBinder_no

12105110 10 101

12105110 12 102

12105110 14 103

12105110 16 104

12105110 17 105

12105110 20 106

If my assumption as to what you require is NOT correct, please post your desired answer.