I was looking for something similar earlier this year and ended up with SOPINE's cluster board. It only supports 7 ARM modules at a time but you can always stac

I was looking for something similar earlier this year and ended up with SOPINE's cluster board. It only supports 7 ARM modules at a time but you can always stack multiple boards. Its also inexpensive. The SOPINE board I have has worked very well and recommend it. https://www.pine64.org/?product_cat=clusterboard https://www.pine64.org/?product_cat=clusterboard