If you already have some kind of Cag maybe consider going for a full drysuit.
I recently bought a dry cag and pants and spent about 300e and this was when there was end of year sales.
The cag and pants are great but some water still gets in around the waist especially if you go for a swim.
I've been doing a bit of checking on the internet and it seems you can get a full drysuit from about €250 up and you will stay completely dry (even when you swim) so I'm told. Check some local shops too. They should have some good deals.
I'm half thinking I should have gone straight for a dry suit at the time but I assumed they would be 700-800 back then. I'm thinking of getting a drysuit now even though I have a decent cag and trousers. You'd still always get use out of a decent cag even if you have a drysuit aswell, i.e. maybe on the sea, racing or if the weather is too warm for a drysuit.
If you are still thinking of getting a cag, I have a YAK Celcius. I find it great, keeps you warm and dry. Paid about €180 at the time.