Now that you have asked this question you should get an LC... cuz people who want a defender; will get a Defender they don't ask questions they are clear in their head!
And practically speaking, sentiments apart... Yes LC in Pakistan would be a better decision in terms of spares availability, technical know how among road side Mechanics, etc. And a well kept 2000 year LC should be fine don't worry about spending time and money in work shops; Japanese reliability is unquestionable but that doesn't make them a better car. A new Defender would still take you to the workshop every now and then since the Pakistani assembled Defenders have serious quality and workmanship issues and yeah parts from the dealer will literally kill you!
A stock Defender is 10x more capable than a stock LC any time! But you don't need that capability to go anywhere in Pakistan, I have been to the North quite a bit we don't have the conditions that would require tanks! Any decent 4x4 makes it with ease. So LC will have no issues whatsoever. And as far as the power is concerned Defender packs some serious Torx and it will never run out of power no matter the conditions... I don't know what engine in the LC you are interested in, I would have done a comparison for you!
I hope I have made things easier for you.. I'm a European cars fanatic and hate Japanese cars with a passion!