Not a kit that I know of, but you can buy the parts to make it happen. I spent many years procrastinating and figuring out the best way for my scene.
You can get a semi- hydraulic kit, then a brake line, and master cylinder of your choice, and put it together. SIP website is a good place to build a wish list of components...
I chose to go with a Stella fork, Motorino Diavolo Master Cylinder, and braided line. Here is a link to what I did:
https://modernvespa.com/forum/post2618976#2618976