Harrier - 2.4/3.5 liter 5 door luxury crossover SUV, average total import cost 35-50 lac
Skyline - 2.5/3.5/3.7 liter mid size coupe/sedan, average total import cost 20-50 lac
Supra - Not in production for the last decade and impossible to import since it's more than 5 years old
Vitz - 1/1.3/1.5 liter 3/5 door small sized hatch, average import cost 8-14 lac
If you want to import and sell, Vitz are hot in the market; for a Harrier and Skyline you'd need to find a rich enthusiast to sell to since there are plenty of other options available in that price range. If you want to get one for yourself get the Harrier, it's far superior to the other cars you mentioned.
If you want a good sedan for the price of the Harrier, look into the Accord CU2 or new Mark X (~40 lac each), they'd have hot potential buyers too.
If you want to exploit the market inefficiency in Pakistan you can import 2007 Camry/Accord/Mark X models for ~18-22 lac and sell for 26-30 lac here which will undercut the market by 2-5 lac and still give you high profitability.
Edit: The Skyline G37 kicks the Harrier in bang and performance, but the Harrier is a crossover SUV which is more suitable for the local 'seth/chaudhry' culture.