Is the PIC capable of sending RAW binary data??
I think if you just send the value without any formatting, it's in raw format.
I.E. X = 10 : HSEROUT [X].

You can send whatever value's in X directly to the USART TXREG like this,
and I'm fairly sure the PIC doesn't automatically convert bytes placed in
TXREG to ASCII;
Code:
SPBRG = 64    ' 19200 bps @20MHz
RCSTA = $90  ' Serial port enable 
TXSTA = $24  ' Transmit enable, BRGH = 1 for high-speed
X VAR BYTE
TRISC.6=0

MAIN:
    FOR X = 0 to 255 
        GOSUB ENCODE
        PAUSE 50
    NEXT X
    X = $0D ' Carriage return
    GOSUB ENCODE
    X = $0A ' Line feed
    GOSUB ENCODE
    PAUSE 100 
    GOTO Main

ENCODE:
ASM
    movf _X, W     ; Load X into W reg
    btfss PIR1,4   ; Wait for TXREG to be empty after last byte
    goto $-1       ; Not empty, wait
    movwf TXREG    ; Empty, so send next byte
ENDASM
    RETURN
I don't have MATLAB to test this, but I can't see why it wouldn't work. I get
the same results from either method with a standard terminal program.