I've got a brand new Dart Marlin windscreen with the 41mm Mounting Hardware that I bought for my 2018 Triumph Speedmaster 1200. Ended up never fitting it as I decided to go in a different direction with the bike. It's never even seen a ride, and is essentially brand new without the box and has been sitting on a shelf in the garage. Asking $100 + shipping. Shouldn't be much for USA as it is small and light.

This is a stock photo attached with the "light smoke". Be aware the one I have for sale is completely clear. Can post pictures if desired.
The 41mm fork mounts fits the original bobber 2017/2018/2019/2020 and the Speedmaster 2018/2019/2020. You can purchase other mount sizes on the Dart webpage. the screen by itself goes for $80. Not ideal, but I could part with just the screen if need be.