(originally posted a week ago) Dear Pomi Saab. You've asked the same inquiry at least 3 dozen times on various threads related to MUTTs / M151s...so I'll try and explain in simple terms, how this thing works.
You have two options...to a) buy from a Thekedar / Contractor or b) buy from a private seller.
In case of option b, you will find the ads for MANY MUTTs on these pages. What I suggest is, that rather than making undue hue and cry about your intent on every page where the word "MUTT" is mentioned...you see which vehicle you'd like to buy, and contact the owner, through a personal, polite, private message. Here, may I warn you that people who have invested time and money in a running project are at complete liberty to demand whatever they WANT for their machine. Which is something you need to bear in mind, when making them an offer. If you and the owner come to some sort of agreement, I'm sure you can exchange numbers / contacts, and finalise the deal in person, or over the phone.
In case of option a, there are a huge number of contractors who pick up these auctioned army vehicles in entire lots from various army depots. These depots are scattered all across the country, so you'll be able to find them (primarily straddling the GT road) at Lahore, Gujranwala, Kharian, Jhelum, Pindi, and Peshawar. Other cities like Multan, Sargodha, Bahawalpur, etc...in short, wherever there is a military presence...will also inevitably have such vendors. The going "rates" for such vehicles is usually pretty stable, and depending upon their condition, the prices of such vehicles should be within 5000-20000 rupees of one another. To be completely certain of the going "rate" you will certainly have to put in some legwork / spadework, at various vendor sites. Such vehicles will also require registration, and restoration from your side. Which should be vectored in, while you make your mind up for your purchase, and the amount of money you want to spend.
Once purchased, there are a number of areas where your vehicle can be built to your choice (and budget). City Sadar road in Rawalpindi, is probably the best place for such modifications and restorations. Lahore's Bilal Gunj is another. Peshawar's Shoba Bazaar is yet another. Owing the the enormous interest in off-road vehicles, nowadays, I'm sure you will find such rebuild artists in other cities, too.
I also suggest you seek some advice from someone knowledgeable on MUTTs, rather than just post your requirement for one, several dozen times over. I'd say that the people on PakWheels are a very congenial and very knowledgeable bunch, and will have a huge amount of good advice to offer you, if they're approached politely, and given due respect.
Best of luck with your intended project.