Hi, i’m looking search and userImportExport plugins for Openfire 3.1.1
You’ll have to check out the code (https://github.com/igniterealtime/Openfire/releases/tag/wildfire_3_1_1) and build it from that.
Note that this is really, really old. I urge you to upgrade.
Or actually it is here https://www.igniterealtime.org/projects/openfire/plugin-archive.jsp?plugin=userImportExport