you need to apply for duplicate physical shares with registrar and transfer agents(RTA) along with your holding details, folio numbers and other details required by them. you can get details of RTA from your company annual reports or BSE website.
Then you will issued supplicate certificates which you can apply for dematerialization and get them into your demat account. The whole process should take about 3 months.
Open a Trading and Demat Account through Dematguru and get additional benefits upto Rs. 2,000/- with no additional charges. Visit Exciting Offers On Opening a Trading and Demat Account – Demat Guru