Not directly, SIP registrations are Layer 3 (IP based) but you can use ‘arp’ (AddressResolutionProtocol) to resolve the layer 2 MAC address of still fresh Layer 3 hosts if they are on the LAN.
To expand on @dicko’s comment - SIP isn’t limited to the LAN, so MAC address isn’t really a thing with SIP. If you get calls from the BBI (Big Bad Internet), you’re not likely to get the MAC address of a device, and I don’t know of any ways to seamlessly add that to the protocol.