I got one a while back from Tractor Supply and it's better than nothing.
Here's a tip, if you get some of these magnets they will screw right into the bolt holes of those black barrel standoff things it comes with.
https://www.amazon.com/gp/product/B01N6KO9R1/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
Then you can put them any height without drilling new holes.
Here's a tip, if you get some of these magnets they will screw right into the bolt holes of those black barrel standoff things it comes with.
https://www.amazon.com/gp/product/B01N6KO9R1/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
Then you can put them any height without drilling new holes.