Any DIT 7.3 will last forever with good maint. I bought mine with 153,000 miles on it. Its a 96 and one of our vendors at work has a 96 with 450,000 miles. He drives 200-300 miles a day delivering supplies and told me they only change oil every 7500-8000 miles. As for price that sounds good for my area.
OBS 7.3's clean with low miles can bring 15k here. I paid 11,900 for mine. I say get it.