For a while now this has not been a big issue anymore, since Planet Virtual Boy member Hedgetrimmer from the UK has created the "Stand Fix kit", which consists of a grey CNC milled solid piece of plastic that replaces the aforementioned medallion on the Virtual Boy stand and comes with all relevant screws, washers and nuts.
The kit is a direct replacement and works just like the original medallion, there's no noticable functional difference except that the replacement medallion is much more stable than the original one; I don't see any chance of this thing ever breaking. Also, please note that the pictured review copy is from the first batch and newer pieces have a nice red color etched "Neartendo" logo on the front (last image). My conclusion: Definitely recommended!
A kit is 7 GBP (about 11 USD or 9 Euro) plus shipping and can be ordered in the Marketplace.
