Hey everyone I am looking for the part that holds up the leaf springs from the top side with the u-bolts. I would like to keep my rubber isolators though. If found these on firmfeel for about $250, is this the lowest price out there?

http://firmfeel.com/Isodeletekit_b73up.htm

Search a parts book here for your part:

http://www.mymopar.com/index.php?pid=107

Find out what other passenger cars used the same part. Then see if you can figure out if trucks and vans used the same part by looking at truck and other parts interchange books at the same site.

Then go looking in junk yards armed with the knowledge of all the models that used that part.

Maybe trucks used a heavier duty version of that part? Anyhow you'd have the option of using it if it fit...

Here is a picture of the part I am looking for

This thread is a little confusing...

The first link you've posted shows the lower shock plate used for eliminating the iso set-up...The U bolts fasten against this plate...You can get those off any 72 and older car...If you're looking to keep the iso then you'll need the lower shock plate off a 73 and newer B Body including Cordoba,charger,satellite etc...
The pic you've posted is a rear sway bar plate using the iso rear...That one goes between the spring and the rear housing...The U bolts pass through that one...
Here's a pic of the 73 up B body isolated set-up using the rear swaybar...

That being said...As you've already found out the factory bean counters really cheesed out on the iso sway bar mounting plate...How they figured the bigger/heavier car would make it with a thinner part than the previous years was a big on their part..
The best chance to find a set of those is either Ebay or hit the boneyards and look for the later {73-79} B bodys... As stated earlier Charger,Cordoba,Satellite etc... Too bad you were'nt closer I know of a few in the boneyards around here...

Here's a comparison pic of the earlier{71-72} B body pieces... Thicker and better designed...Note the small leaf spring centering pin hole..The iso plates are easy to pick out when you see the difference...

Hey thank you for the pictures and detail about the differences of the two parts. I was just unclear what the name of the plate was. ANd do you know the name of the junkyards out your way? I am in the need of a little road trip.

I'll get the contact and location info on them and shoot you a PM..