It wouldn't be hard to get your loot back after the module is over. Just run another (non-stripping) module with the toon before the item-stripping module and put the loot in the first convenient container at the beginning of the module. Save the game. Then, after playing the item-stripping module and saving the toon at the end, open the saved game in multiplayer mode and use the newly saved toon. His stuff from the earlier version should be in the container.
Of course, that doesn't let you use those items while playing the premium module. For the most part, that should be fine, since those modules were designed so the PC would not have imported items.
There are probably a few ways to get access to items during the premium module, too. I don't recall when exactly the premium modules do their item strips, for those that do. If they do it after some delay (say, after an opening cut-scene), then one could run an override script from DebugMode before the strip that would store the items in the campaign database, just looping through with StoreCampaignObject(). Then, after the item strip, get the items back with a companion override script that loops through with RetrieveCampaignObject(). Clunky, but it should work. I assume that there would be a way preserve items in magic bags and so on, too, but that would require a bit more effort in the script. It would probably be a good idea to have a third script that cleared the items from the DB, too, since the first script could really result in an unnecessarily large DB.