Not all HP cd/dvd drives are proprietary. Most (not all) laptop cd/dvd drives are 12.5mm drives. You can measure the face and if its 12.5mm then chances are you have a standard drive. Note most IBMs use a shorter drive.

I assume that your laptop is out of warranty.

Try to google a service manual for your HP. It should show how to remove and install your drive. I was able to upgrade my laptops (HP NX6125) cdr to a dvdr by DIY. Just bought a dvdr from a guy I found in buy and sell. Cost me 3500 pesos. Tools needed were a paper clip, T9 or T8 torx screw driver and a philips screw driver. Replacement and installation took less than 10 mins.

Or you can try to have it repaired or replaced in Mega Mall. There is a kiosk there that speciallizes in laptop repairs. Have not tried them myself though.