You can hunt around through the kernels that come with Red Hat 7.3 until you find the best fit.
You can go to www.kernel.org
and download the latest stable kernel source. Do your own kernel compile. The first time you compile your own kernel it will be hellasiously complicated. It will take you several tries to get it right.
When you are finished you will have a kernel that is more stable, smaller, and faster than any of the canned Red Hat kernels. In the process your knowledge of Linux will take a quantum leap upward. You will also learn how to manage frustration.