Based on my recent searching, Montero prices are all over the place across the map. If it runs and looks as good as you say, your price sounds decent to me. If you have a u-pull-it near you, I would change out the A/C compressor. The less it needs, the easier for the prospective buyer.

Your 2003 is a 3.8L...

Big Truck: 00, 3.5, Endeavor, 5-Spd drive line in hand!
Little Truck: 87, 2.6T I/C, MT, LSDs, Tonneau Top
Her Truck: 03, 3.8, 20th Anniv, 65k
Daughter's: 06 Eclipse, Keeping it Mitsu!
FSMs: MitsubishiLinks.com