I'm backing up a number of Oracle databases to Netbackup (via Oracle RMAN). We have two sites:
(A) where the databases and main Netbackup media servers are located
(B) a remote site where a single Netbackup media server are located

The Netbackup media server at site A has disk staging, so the backup goes to disk on that media server before eventually being staged to tape.
Straight after the backup at site A is made, the backup is copied by Netbackup to the media server at site B.

We need to do regular restores at both sites. But for restores at site A I'd like to use the media server at A. And for restores at site B I'd like to use the site B media server. This is because the network link between the two sites is slow and the databases are large.

From within RMAN I'm allocating channels for restore like this:

allocate auxiliary channel 'tapedev1' type 'sbt_tape'
  parms="BLKSIZE=1048576 ENV=(NB_ORA_CLIENT=ora-patrlp01-b,
  NB_ORA_SERVER=netbackup, NB_ORA_POLICY=Prod_Oracle_PATRLT01)"

Does anyone know if it's possible to specify the Netback backup copy number within the parameters that RMAN passes to Netbackup? That'd allow me to get the backup from the correct site.

I'm aware that some backups can be promoted to primary but if I do that then both sites would restore from the same backup file (which is what I'm trying to avoid).