Work Sharp Alternative Diamond Whetstone Holder

Wanted to use different (and much cheaper :) ) diamond whetstones in my Work Sharp Benchtop knife sharpener which I really like. 
Adapter is designed to insert 160x20mm magnetic baseplate for 150x20mm diamond whetstones. These can be easily obtained on Aliexpress (i.e. https://www.aliexpress.com/item/1005003738593179.html?spm=a2g0o.order_list.order_list_main.250.3e7a18029CLrJO)

Magnetic baseplate is secured by three small screws with washers (or larger head).
It can be tight fit, I had to sand one magnetic plate a bit.

Also uploaded Fusion 360 file if you'd like to modify.