The disc will clear the wheel, but the caliper will still hit the wheel.

Yes, other discs can be made to fit. Mainly larger discs that are cut down to the same diameter.

Perhaps you could use a 280ZX rear 258 mm rotor which fits over the B310 hub (no machining needed) and use a custom bracket to mount the S13 caliper farther down. The 258 mm rotor fits under most 13" aluminum wheels when using the Pulsar caliper (see 280ZX Brake Upgrade).