What is the best way to connect 2 Sans together tht are about 800 metres apart, within the same physical building (hosptal) for the purposes of replication.

Have the following:

Site 1 has 2 Silkworm 24000 switches with a Clariion attached an a few hosts.

Site 2 has 2 Brocade 200E's again with a Clariion and some hosts attached.

I want to replicate from 1 Clariion to the other, and have a resilient network.
Each site has 2 fabrics configured, how many more should i configure ?
Should I buy any additional switches, Directors or just connect the existing switches together ?