Dear Dhruv,
1. In standard you can set filters for sales org(KNVV-VKORG), distribution channel (KNVV-VTWEG), and division (KNVV-SPART) . These should already be contained in SMOFFILFLD so you do not need to add them.
Please refer to the following picture.
2. If you want to only replicate customers for a particular sales area and prevent customers from other sales area to be replicated to CRM, you also need to set the flag "Filter Cust. Completely" in ERP Tcode PIVV.
Best Regards,
Ellen Feng