9500 Pro isn't flashable to 9700. It's already got 8 pipes, but it's only got the 128bit memory interface vs. 256 bit in the 9700 (and 9500)
And to anyone who's interested, here's an update on what's going on with some of the Radeon 9600 Pros.
I bought a BBA (built by ATi), believe it to be OEM but that's beside the point. It's evidently fairly new and...
Out of the box, core was only stable to around 450MHz. Ram was 3.3ns and would OC to ~324MHz.
Out of the box, the RAM is running a lower latency than is recommended by Samsung. It's also running at lower than maximum voltage. It's suspected but not concusively proven that the first batch of 9600 Pros were running with a higher Vcore than the current models are. Mine, out of the box, has a Vcore of 1.25V. There's a fairly simple voltage mod you can do to the card, bumping it up to 1.4. I'm still testing mine, but so far it's looking like I'll be running at or close to 500MHz.
Honestly, I wouldn't recommend a 9600 Pro now unless you get a really good deal on it. These aren't the overclockers than the reviews and the first batch indicated them to be.