You could have used a Seymour Duncan Woody and connect a wireless transmitter to it and place that inside the guitar.
Very easy to install and remove and no need for drilling out the guitar for a jack.
If you only need small pieces, look into picks, f.x. Fender Heavy.
I just ordered some for my fretboard dots on my 1947 ukulele restoration.
Some pickguards are also announced as being celluloid.
For white, you can dissolve tabletennis balls and pour it into the engraving or into a mold.
Yes, the head with tuners is very heavy and not supported at all in the case. On top of that, the neck is supported just where it is weakest.
It's like a man falling on his back on a table, with his head over the edge.