Pretty much the intersection of SimLibrary.get_stub() and SimSyscallLibrary.get().

        :param number:      The syscall number
        :param arch:        The architecture being worked with, as either a string name or an archinfo.Arch
        :param abi_list:    A list of ABI names that could be used
        :return:            A SimProcedure representing a plausable stub that could model the syscall

def get_stub(self, number, arch, abi_list=()):
        """
        Pretty much the intersection of SimLibrary.get_stub() and SimSyscallLibrary.get().

        :param number:      The syscall number
        :param arch:        The architecture being worked with, as either a string name or an archinfo.Arch
        :param abi_list:    A list of ABI names that could be used
        :return:            A SimProcedure representing a plausable stub that could model the syscall
        """
        name, arch, abi = self._canonicalize(number, arch, abi_list)
        proc = super(SimSyscallLibrary, self).get_stub(name, arch)
        self._apply_numerical_metadata(proc, number, arch, abi)
        l.debug("unsupported syscall: %s", number)
        return proc