Dunlops are good and easily available in 12" and 13".
Yokos are a much better option but I dont think that you will be getting a huge variety in these rim sizes so Dunlop ECO or Le-mans would be good.
About price I have no idea about Karachi market but just to give you an idea I got Dunlop ECO for 2850/piece in February in 165/70/12 size in Rwp.
In 165/65/13 165 is the tyre width, 65 is the profile (the rubber part) and 13 is the rim size.