Generally when you buy a RedHat license, you get access for one year to their repository. In otherwords, access to RedHat specific packages is by paid license ONLY. Your company should have access to these packages, so you'll have to ask your company systems administrator for registering your system properly to obtain such packages.
However, as you know Centos is built from the non-proprietary sources of RedHat and many packages are available. Thus their repository COULD be viable and useable in a RHEL system.
Of note, RedHat backports patches into their RPM repositories without necessarily changing the major/minor version. Thus what might appear to be an older RedHat RPM version might indeed be up-to-date using patches.