Definitely enough. Nigella in Domestic Goddess has a recipe involving only 250g. Here it is (you can easily adjust it without very difficult maths!!):
250g raspberries
250g caster sugar
Preheat overn to 180 centigrade
Put raspberries and sugar in separate oven-proof bowls
Put both bowls in the oven for 20-25 mins until really hot
Take out of oven carefully and add sugar to raspberries
Pour into a very clean jar (you can sterilise with boiling water, or by taking it out of a dishwasher as soon as the dishwasher has ended).
Cover and cool.
I don't think you need to use special pectin sugar - some fruits need it and some don't. My other raspberry jam recipe is this:
Equal quantities raspberries and normal sugar.
Put raspberries in a pan and slowly bring to the boil.
Add sugar gradually and stir until dissolved
Bring to boil and boil hard for 3 mins, stiring constantly.
Cool slightly, pour into jars etc.
Good luck.