How to list files with specific extension with long path name without waiting hours in PowerShell

Question

I need to list recursively all files in a UNC path with a specific extension (.PST).

I have tried this:

Get-ChildItem -Path "\\DFS.LAN\users\*" -Recurse | ?{$_.Name -like "*.pst"} |
    Select FullName

Some errors appears (path too long), how can I deal with it?

Get-ChildItem : Impossible de trouver une partie du chemin d'accès
'\\DFS.LAN\users\User1\Documents\...'.
Au caractère Ligne:1 : 1
+ Get-ChildItem -Path "\\DFS.LAN\users\*" -Recurse | ?{$_.Name -li ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : ReadError: (\\DFS.LAN\users...:String) [Get-ChildItem], DirectoryNotFoundException
    + FullyQualifiedErrorId : DirIOError,Microsoft.PowerShell.Commands.GetChildItemCommand

EDIT

After a little search, it is possible (with PowerShell 5.1) to avoid error with long path name like this:

Get-ChildItem -LiteralPath "\\?\UNC\DFS.LAN\users\*" -Recurse |
    ?{$_.Name -like "*.pst"} |
    Select FullName

Explanation Here

Example

Get-ChildItem -LiteralPath '\\?\C:\Very long path' -Recurse

For UNC path, this is slightly different, the prefix being \?\UNC\ instead of \

Get-ChildItem -LiteralPath '\\?\UNC\127.0.0.1\c$\Very long path\' -Recurse

Is it possible to inscrease the speed of this listing?

EDIT

Maybe using the -Filter parameter increase the speed of this task ...

Get-ChildItem -LiteralPath "\\?\UNC\DFS.LAN\users\*" -Filter "*.pst" -Recurse |
    Select FullName