HSRP and IPSEc tunnel

I currently have two locations connected over the internet via IPSec tunnel. All kit is Cisco.

One of the locations has recently been upgraded, and there is a now going to be a two tier redundant architecture in play (doubling up for failover). There will now potentially be two routers at this site using HSRP to provide a redundant path for LAN traffic. The other branch will remain the same with a single router.

What is the best way to design the site to site with one of the sites having two routers and the other having one? Will the two router failover site require two internet connections also? If nothing else, I'd like to be able to convince them to stick with the one router as each site

Thanks.