Hi,
You can set up a Site to site dynamic to static indeed, take a look to this link:
-http://www.firewall.cx/cisco-technical-knowledgebase/cisco-routers/936-cisco-router-vpn-dynamic-endpoint.html
On the router that has dynamic IP address, you will need to configure the static config, and on the static IP address side you will need to configure the dynamic config.
Hope this helps!
Please proceed to rate and mark as correct the helpful Post!
David Castro,
Regards,