2. The bills showing the costs of examination or treatment or records of a treating or examining health care provider as defined in § 8.01-581.1 or a health care provider licensed outside of the Commonwealth for its treatment of a party or child outside of the Commonwealth. Such provider's records or bills shall be admitted if (i) the party intending to present evidence by the use of records or bills gives the opposing party or parties and, if applicable, the guardian ad litem a copy of the records or bills and written notice of such intention 30 days in advance of trial and (ii) attached to the records or bills is a sworn declaration of the custodian thereof that the same is a true and accurate copy of the records or bills of such provider. If, thereafter, a party or guardian ad litem summons the health care provider or custodian making such statement to testify in proper person, the court shall determine which party shall pay the fee and costs for such appearance or may apportion the same among the parties in such proportions as the ends of justice may require. If such health care provider or custodian is not subject to subpoena for cross-examination in court, then the court shall allow a reasonable opportunity for the party seeking the subpoena for such health care provider or custodian to obtain his testimony as the ends of justice may require.