Joso,
The currently-available upgrade (I hesitate to call it 'replacement') for the Centrino Wireless-N 1000 card is the Wireless-AC 7265 card. It is important to get one that is marked '7265HMW'. There is another version, marked '7265NGW', that is for the M.2 socket and you do not such a socket.
Now, I must caution you. In some case, we have found that the laptop manufacturers have included inclusion or exclusion lists in their BIOS that attempt to restrict you to purchasing through them. You thus need to check with your laptop vendor to see if this is the case. You wouldn't want to purchase an upgrade component and then find out that it won't be allowed to run.
Hope this helps,
...S
