I managed to get the problem handled and now I can read and write 5 byte data blocks to and from the TEA5767.
I just want to say thank you to Tim S. for jogging my stalled thought process, Tim H. for suggesting the use of memory blocks and John for providing the idea of writing to the file descriptor.
This is essentially the code did the trick for me:
Dim mbRadioOut As MemoryBlock
Dim fdRadio As Integer
Dim bsRadio As BinaryStream
mbRadioOut = New MemoryBlock(5)
' Initialize the radio.
'
mbRadioOut.Int8Value(0) = Integer.FromBinary("10101001")
mbRadioOut.Int8Value(1) = Integer.FromBinary("11010100")
mbRadioOut.Int8Value(2) = Integer.FromBinary("10110000")
mbRadioOut.Int8Value(3) = Integer.FromBinary("00010000")
mbRadioOut.Int8Value(4) = Integer.FromBinary("00000000")
' Get file descriptor of radio.
'
fdRadio = GPIO.I2CSetup(&h60)
' Open a binary stream to the radio.
'
bsRadio = New BinaryStream(fdRadio,BinaryStream.HandleTypeFileNumber)
' Write data to radio.
'
bsRadio.Write(mbRadioOut)
Reading the data from the radio was essentially the reverse of the above.