Oracle Linux is nothing but a recompiled/repackaged RedHat Enterprise Linux with Oracle "thingies". The below site contains a full list of supported hardware:
Certified Hardware
Unfortunately, I did not see any SPARC based hardware. I don't think OEL supports SPARC as they have it even before SUN merged. As far as RedHat is concerned, it sells Linux only for Intel and Power architectures. Not sure, but RedHat Linux 7.6 (not RHEL) was the last one to have SPARC supported.
You may be able to find some discontinued distros like Aurora SPARC Linux based on Fedora Core 3.
What is your intention by the way?