Unfortunately last year the DMU Server facility caught fire so the entire server had to be reset in a new machine. This caused all players to lose purchased items as well as everything else they owned on the servers.
SWDTeam did their best to replace the store purchased I tems however I believe John (1WTC) had to do a cut off of 2 years otherwise he would have to go back over the last 9 years or so of dalek mod to reimburse items lost.
All TARDIS Exterior chameleon circuits now have crafting recipies that can be used to craft TARDISes on the DMU Server - so I would recommend possibly doing that to get your tardis exterior back.
I hope this helps!