I also sell cheap $150 10 Gbps and 25 Gbps QSFP28 switches but they are only partially open source.
They still sell some of the NetFPGA models, very pricy [2].
There are a few Chinese and Russian switches but you can't buy them anymore because of the war.
[1] https://www.researchgate.net/profile/Merik-Voswinkel/publica...
[2] https://netfpga.org
How big is it physically? I don't really get it from the link.