Hello, Ms. Sun, since the train tickets can only be purchased from its departure city, it is impossible for you to get it from Malaysia. You can buy the train tickets in the railway station once you get there. It will cost you about CNY152.00 net for the round D train Hangzhou/ Shanghai/ Hangzhou for the first class tickets.

Do you mean you will arrive in this Wednesday, Nov 25? If you arrive at 13:10 in Hangzhou, you can take a taxi or the shuttle bus to the railway station to take the D train. Since the D train are very frequent between Hangzhou and Shanghai, say, D5656 1650/1838, it may not very hard to get it. Good luck!