Go for a G100 if u can find a clean and original one. Check the florrs and body for rust. It should prefereably be atleast 60-70% original paint.
If u can find an original G11, it wud be much cheaper and a helluva lot of sturdy machine.
I have had a G11 for 7 years now and runnin on CNG. Its taken me to mountains and highways with a/c and CNG. Awesome machine.
Parts are no problem. Even if u dont find sumthin, it can be fabricated into it. Alto, Khyber and Mehran parts can be made to fit onto it.
Mail me if u need any info.
Peace