I read the recent post by HP_Cuda and realized I am in the same boat. No jack or jack parts were in my 70 Challenger when I bought it. I don't need a pristine jack and hope a member might have one or a line on one at a reasonable price. Thank you.
When buying the bumper make sure you get the correct hook. I bought a 70-71 challenger jack from ebay and it came with a 70-71 cuda hook number 2931101. It has a different curve where it touches the bumper, but looks like it will work. Open to trade my cuda hook for a 2931102 challenger hook.
A 70-71 challenger uses hook number 2931102
70-71 cuda with colored bumpers uses hook number 2931101
70-71 cuda with chrome bumpers uses hook 2931100
check out this site for all the jack info you'll need.
http://www.nicksgarage.com/jacks.htm