Need advice on purchase of 76 280 CE
 

I am thinking of buying a 76 280 CE from a local clasic car dealer. The car shows 34,000 ( I am assuming actual miles to be 134,000). The car is very clean in and out and it drives good for a 30 year old car, other that the AC doesn't work ( there is no belt on the compressor). What kind of problems should I look out for. Is the timming chain an issue and how big of a problem is the air conditioner on these cars.

Thanks in advance for any advice.