We used to have an AM4-campaign where we gave away free AM4-brackets to users, but ended it a few years ago when the Kelvin-series was discontinued.
These brackets are however still available for purchase through Aquatuning: https://www.aquatuning.co.uk/water-cooling/cpu-water-blocks/cpu-spare-parts-accessories/21553/alphacool-eisbaer/be-quiet-silent-loop-bracket-for-radeon-ryzen-s.-am4