How to retain the current value of a sequence when copying a database in SQL Server
You can get the current seed values by running:


SELECT 
   s.name as [schema],
   t.name as [table],
   IDENT_CURRENT( s.name + '.' +t.name )  NextIdentValue,
   'DBCC CHECKIDENT ('+char(39)+s.name+'.' +t.name+char(39)+',RESEED,'+ CAST(IDENT_CURRENT( s.name + '.' +t.name ) as varchar(50))+ '); ' as cmdSQL
FROM sys.schemas AS s
INNER JOIN sys.tables AS t
  ON s.[schema_id] = t.[schema_id]
WHERE EXISTS 
(
  SELECT 1 FROM sys.identity_columns
    WHERE [object_id] = t.[object_id]
);


Run the cmdSQL script column on the target system.

Depending on your requirements, you can store the output to a table/file and then execute the synchronization script after restore.