While you can download a version 7 converter and open directly (other than on a current Mac)... the version 10 converter can open version 7 files, and convert them to an integrated file that you can then open in AC 23 or other recent versions. (A version 7 project will contain separate project and plot maker files.)
One of the forum moderators AC 28 USA and earlier • macOS Sonoma 14.7.1, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB