Hi Staciej0,
You can use the VMware Converter to go From your vCenter to your vCenter, the destination should be your vCenter not your SAN directly.
From there once you have selected your vCenter as a destination you will be able to see the datastores, select one of those.
You can clone your vCenter.
When you get to the disk options in the conversion process there will be a "Advanced" option this will allow to select Block Level or File Level Cloning of the disks you want File Level that way you can select your size.
Cheers
@iiToby