If they are aware of the existence of a SAR, they can likely pull it themselves. However, taken from the latest "Security Officer's By-Word", published by The Kansas Bankers Surety Company:
"Part (ii) of the same regulation makes what appear to be the only exceptions for disclosure. Under Part (ii), provided no person involved in the transaction is notified, banks can disclose the SAR and its existence to FinCEN, Federal, State, and local law enforcement, and certain Federal or State regulatory authorities."
That tells me that you certainly may turn that over as part of a subpoena request. It may also be interpreted that a subpoena would not even be required for information to be shared to law enforcement.