U can get hold of any Garmin NUVI GPS from Pakistan or get it from abroad.
Visit this site
PK Maps • Index page
Get registered, they make Garmin GPS maps, it is a free forum.
Download the map into GPS & bingo.
At present 11 cities are covered.
The Maps are free.
This is what I done.
Bought Garmin NUVI 255W from USA & downloaded the maps.
Later on if u feel then u can buy Maps from Naqsha.net which are more detailed.