Combine the cream cheese and sour cream in a bowl, using an electric mixer set at medium speed, until smooth and fluffy. Add the sugar and eggs blending well. Pour into the unbaked pie shell. Bake at 190ºC . for 35 minutes or until a knife inserted in the center comes out clean. Chill for at least 1 hour in the refrigerator. Meanwhile, drain the raspberries, reserving the juice. Add enough water to the juice to make 0.75 cup of juice. Blend the cornstarch and juice together in a 2 litre saucepan. Cook, over medium heat, stirring constantly, until the mixture comes to a boil. Cook for 1 minute more. (Mixture will be very thick.) Remove from the heat and stir in the raspberries, then cool to room temperature. Fold the whipped cream into the cooled raspberries and spread the mixture over the chilled cream cheese layer. Chill for an additional 2 to 3 hours before serving.