Hi Ashutosh,
I am trying to answer this without exactly knowing the real use of what you are intent of SPQ information duplication is. If you are going to use the SPQ information to build your vendors in upstream (i.e. Ariba Sourcing2Contracts) you are probably deviating from the best practice. Single Supplier Organization profile in Ariba can hold multiple addresses and multiple supplier contacts . Also, you can set supplier Org A as parent to Supplier org A1,A2,A3. Ideally if A,A1,A2,A3 are different legal entities then most often than not their basic profile information will always differ so duplication will not help.
If you are wanting to add a supplier in order to send a PO to them then you are wanting to create a supplier in Ariba downstream (P2P). Please note that the supplier object in Ariba is completely different in Upstream and Downstream and they do not have any direct relation technically.
Regards
Vilas