What FPGA vendor has 2 CAN hard IP blocks? I don't think I've ever seen such a device before.
Usually an FPGA doesn't have much hard IP beyond multi-gigabit transceivers, PLLs, DSP blocks, block memroy, PCI end points, and perhaps a processor core. Are you sure you aren't confusing FPGAs with a microcontroller with integrated CAN?
If you want one or more CAN controller(s) you have to implement them in the FPGA fabric logic, therefore you are only limited by the number of controllers that fit within the device resources.