I don't actually believe there were any literal golden toilets, but rather that the term was a hyperbolic description of pork barrel spending. It's basically a meme from last century.

This article casually mentions it https://www.chicagotribune.com/1992/08/30/everyone-knows-about-the-pentagons-gold-toilet/

but sadly it's paywalled... here's another though

https://www.latimes.com/archives/la-xpm-1986-07-30-vw-18804-story.html
--look at that date! that article is almost as old as ME!