The only other three things I can think of are:
(1) Permatex 3J (or 3H or 3D, same stuff just different size containers)
(2) RectorSeal No. 7
(3) Seal-All (made by the same people who make Goop)
The RectorSeal No. 7 is a plumber's putty that is pretty expensive, more than $30 for sure. I'd try anything and everything before this.
I'd go to your local auto parts store and read the differences between the Permatex and Seal-All. I have used the Seal-All and it didn't work for my purposes as I was trying to seal two pieces of my plastic gas tank together... and apparently, that's the only thing that Seal-All doesn't work too great on -- shiny plastics. It'd prolly work for your situation a lot better than mine because I was trying to secure the mount to the gas tank, which means the Seal-All suffered from heavy vibrations and extra pressure as this hole was near the bottom of the tank. I filled it to the top, and it didn't leak for a couple hours, then slowly it started dripping a drop at a time... then the next day, my tank was nearly empty.