SSL Solution for Multi Domain / Multi Host

I need to secure a couple websites, and am looking for the ideal SSL solution to handle multiple domain names / multiple hosts. Here is a breakdown of my topology.

Website 1 - Self hosted IIS server. This server has multiple IP addresses (3 different ISP connections) and host names, but all point to the same exact virtual machine, aside from a replica that is stored at a remote location, but would need to be able to come online as a failover.

website1a.com - points to 1.1.1.1 (onsite IIS Server)
website1b.com - points to 2.2.2.2 (onsite IIS Server)
website1c.com  - points to 3.3.3.3 (onsite IIS Server)
website1d.com - points to 4.4.4.4 (offsite backup of IIS server)

Website 2 (Wordpress) - GoDaddy VPS hosted, with Name Cheap backup website
website2.com - points to 5.5.5.5 when there is a fail over, I auto redirect the DNS for website2.com to go to NameCheap Hosting 6.6.6.6

I was thinking about purchasing a single SAN SSL that includes every domain. However, I am not sure I will be able to install that SSL on the IIS server, as well as the go-daddy and name-cheap hosting.

Looking for advise.

Thanks in advance!!
Dan