GLolas has it right. I had to wait to order until December when the 48re was available, to get the HO/automatic. Some thought the 47re would still be used with the SO, but once they had production of the 48re going they stopped the 47re production. They used up the stock of 47re transmissions in SO trucks but that did not last long. If you see a 47re on the lot, it has to be an SO and was on the lot about 6 months now.
I would not accept a 2003 with a 47re now at less than a $3000 discount from the 48re price, and then take it for a rebuild/upgrade right out of the box if you plan to do any pulling. In fact, at this point I would order a 2004 if I did not already have a truck, because the '04 has an improved 48re that should be ok with an e-brake.