Hi Mass,
Document talks about load balancing packets across 2 links.
http://www.trapezenetworks.com/techpubs/en_US/junos13.1/topics/example/security-chassis-cluster-single-srx-series-configuring.html
Yes , you should be able to configure this on the Chassis cluster as well.
Replace Normal Interfaces on the vpn configuration using reth interfaces for clustered setup.
Regards
rparthi
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