The PV I bought a few years back had the very same problem, a big ugly hole in the dash where a replacement radio was installed. The dash pad was also in bad shape. I was real luck to find someone with an unmolested dash and real good dash pad so I painted the replacement ad installed it. Then I found an original radio here on the brickboard. The dash looks great.
It might be worth hunting around for a replacement dash. They are not that bad to remove but somewhat time consuming. It is not one of those jobs most people will do very often to get efficient at.

Good luck with the project.
Dennis C