Do you mean the differential ring and pinion gears, or do you mean the rack
and pinion for the steering?
Let us know which you mean, and we can give you some guidance on where to get them. Most aftermarket parts you can get from Rock Auto or the usual chains. Some parts you can find OEM from dealers selling on eBay at good prices. But, again, it depends on which part you want as to the best sources.
To find the Chrysler part numbers, you can download the parts pdf’s here: https://www.dodgeintrepid.net/113-se...s-catalog.html
It’s a good idea for part numbers with a leading zero, to try searches with and without the leading zero, as some sources will only recognize the factory part number one way or the other, but not both. On eBay, you can handle that with one search by putting the part number with and without the leading zero in parentheses separated with a coma, i.e. “(Chrysler, Dodge) (056789B, 56789B)”. The letter at the end is generally a revision level of the part and usually should be whatever the last one available is, not necessarily the one listed in the parts pdf, and may not be easy to determine, or try the search without the last letter.
Let us know which parts you are searching for.