Sounds like you're running a standalone 2200 on R75.40: Gaia or SecurePlatform?
For the cluster you are upgrading to, do you have a separate management server or is the management server for the new cluster also to be on the gateways (i.e. using a Full HA configuration)?
In general, you are going to use the Migration Tools for R77.30 on your existing R75.40 system.
Which exact tool will depend on whether your gateway is:
Gaia should be used for your new appliance.
You will use the migration tools on the new appliance to import the existing security configuration.
The OS configuration will depend on whether you are already on Gaia (see Export / Import configuration / partial configuration in Gaia ) or on SPLAT (See Migration from SecurePlatform OS to Gaia OS)
For Full HA config, see also: How to install Full HA cluster on Check Point appliances