Dear Venkatesh,
This can be achieved as follows:
Step 1: Maintain the new condition records for the price through the T-code : VK11.
Step 2: In Copy Control, Delivery to Billing ( VTFL) , at item level change the pricing type to 'B' - Carry Out New Pricing. This will determine the new price in the billing document as on date.
Thanks & Regards,
Md Faiz Abbas.