The IH part number is 1837872C93 and I originally purchased them from a local IH dealer for $500 (approx). However, after some research yesterday, I returned them because I found a cheaper set that is very similar for a lot cheaper.
I ended up using the Dorman 679-005 kit. It was less than 1/2 the price of the IH kit and I was able to compare them both side by side before deciding to go with the Dorman kit.
The only real difference was that the IH kit had a few more baffles in the flex sections than the Dorman kit. Other than that they were very similar.
Rockauto, Amazon, eBay - all have good pricing on the Dorman kit. The best pricing for the IH kit is probably on the dieselorings site.