Tom West https://urgthrash.wixsite.com/squirrelmaster - a decent stock (better than anything I can make) but not as high quality as the next two I listed below but much nicer than the plastic 1399 stock you get with the Prod. He offers different type woods. Mine is walnut and I like it. I have a Tom West stock on my 1720T as well.
Rink-Formgriffe https://www.formgriffe.de/en/Shoulder-stocks/ - another quality made stock. Make sure you get it with the adjustable cheek riser. It will be too low otherwise. I like mine a lot. The forearm on mine is not made by Rink. I got that piece on eBay a couple years ago. I believe it’s made in Germany.