This could be the first 100% accurate replacement for the original control stick design.
http://www.nintendoworldreport.com/news/42033/nintendo-64-control-stick-replacement-parts-being-kickstarted
For a long time now, enthusiasts of the Nintendo 64 have been searching for ways to replace worn out control sticks in their controllers. Finally it seems, someone has undertaken the challenge of completely recreating the original parts.
The Nintendo 64 control stick mechanism was of a mechanical design, it utilised a few plastic gears along with the stick itself moving around inside. These physical movements and positioning of the gears and stick were then translated into the digital input information for the controller.
This poses a problem however; with mechanical parts moving and grinding against each other they slowly wear down and cause the control stick to lose its firmness and full functionality. Aside from the gears that wear, the control stick part itself also rests on a small plastic bowl that is also subject to wear, causing the all too familiar white dust to leak out of the controller.
Enkko is going to be reproducing the stick and bowl so that N64 fans can fairly easily restore their controllers. For now, they are not going to be producing the gears, but seeing as how the Kickstarter has already been funded, a stretch goal for the gears is apparently under consideration and if produced will be provided to backers at no extra cost. The gears will be delayed in shipping as construction and testing will take longer for those.