I can't believe the VW guys missed this.
@munawar69, it is recommended that if you have a stock engine, stick with the stock drum brakes. If they are setup right, they perform well and are enough for the car.
If you really want to go for disc brakes, the best option would be to find a set from a VW Variant at Shershah. You can also ask the VW-only mechanics as they might have some or might know of someone who has them.
You can also try sourcing from other cities.
About EFI...well on a Bug, EFI would be setup like any other car. You would need the basic components like injectors, sensors, fuel pump, throttle body etc.. But the main thing, and the most difficult to get, is the ECU, or the 'brains' of the system.
ECUs from other cars might not work. If you are interested, then have a look at MegaSquirt. This is a programmable ECU which can work for pretty much any setup. It comes as a DIY kit and is relatively cheaper than other programmable ECUs. Check it out at megasquirt.org
I have some pages bookmarked where people have done EFI conversions on their Bugs. I'll post the links soon here...