They don’t do private requests. There is a server transfer feature but you cannot be overencumbered during the transfer. So you need to get get as much carry capacity with as much encumbrance points you can get and see what you can fit in there. If you have some friends who are willing to transfer some stuff for you, this may also help.
Here is the post about it with additional info (note the part with losing your buildings and thralls if you are the only member of the clan):
If you happen to be on a server that will close, you may be lucky.
https://forums.funcom.com/t/trimming-official-servers/188375