The 2 tensioner pulleys for the alternator are available aftermarket. NAPA P/N ATM 155-3401, these are designed like the OE so no modifications are necessary. Gates P/N 38042 will also work for cheaper. You'll just have to stack 5 8mm washers behind them to space them correctly. I've used both with good results. The one for the AC that's on the drivers side is only available OEM Mitsu or salvage.

Fasteddy's advice is occasionally sound...