Why not just rebuild the one you have, or get another Monty 3.0 24V? Nothing is "perfectly compatible," though there are other possibilities.

Start with a search on this one, as it comes up on a quarterly basis. Especially look at posts by FrankR and OldColt.

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