Used Parts you can get are: (from a DOHC of course)
*Head with cams and valvetrain
*Intake manifold
*Exhaust manifold (or DOHC header)
*Intake assembly (why not go with an Iceman or 3.0L intake?)
*EGR valve tube
*Pistons (you can use SOHC pistons, but you will lose compression)
*Fuel rail and injectors
*Passenger side motor mount bracket
*Valve cover
*Cam gears
*PCM for your year of car, 95, 96, or 97-99 (why not get a Mopar PCM?)
*Power bulge hood or cut the bracing out of your current SOHC hood.
*You can opt for the dual radiator fans, but I don't think you need them even if you have A/C
New parts you should get will be:
*DOHC Headgasket kit
*Timing belt/timing belt covers (if you want them)
*Timing belt idler pulley
*Plastic thermostat housing
*Upper radiator hose
*Camshaft position sensor
*Spark plug wires
*Head bolts
*New gaskets where you will need them.
*I'd also suggest changing the water pump while you are at it, along with the new timing belt and tensioner pulley
You will also need to extend the 3 CTS (coolant temp sensor) wires so that they reach it's new location.
I doubt you can find a new one. You may be able to find a rebuilt one. Price....depends on where you are buying from.
If you have a Mopar PCM, you should run premium gas all the time.