I found my jack parts on ebay. Just search different combinations of challenger jack spare tire, etc etc. Took me weeks of looking, lurking and bidding before I put it all together.
Got to do your research before though because there are so many different types of jacks, and if you are into originality you absolutely MUST research because otherwise you will not get the type parts you need. Some of the hooks, bolts and other metal parts are repopped