Hi Sprout,
Unfortunately, there is no specific example for BGP over IPSec.
Below are the basic steps of configuring a BGP over IPSec.
1) Configure the IPSec tunnel.
https://support.huawei.com/hedex/hdx.do?docid=EDOC1000163385&id=dc_cfg_ipsec_0052&lang=en
2) Configure the static route for the BGP peer addresses with the IPSec tunnel as the next hop.
https://support.huawei.com/hedex/hdx.do?docid=EDOC1000163385&id=ip_route-static&lang=en
3) Configure the BGP peer through the static route.
https://support.huawei.com/hedex/hdx.do?docid=EDOC1000163385&id=dc_cfg_bgp_0068&lang=en
I hope it helps.