I’m not sure whether you are using restricted data (e.g., in an RDC environment) and therefore can’t use IPUMS data for your purposes, but it’s possible to merge CPS data from IPUMS with CPS data from the Census Bureau, which would allow you to attach the HIU variables to the original data. See this blog post on how to merge IPUMS CPS data with other versions of CPS data. As discussed in this IPUMS forum post, you can complete this merge with a smaller set of linking variables in samples after May 2004. We also offer source (original) variables via IPUMS CPS. You can view these by toggling to unharmonized variables in the IPUMS CPS extract system.