What is the opinion of Reddit about the
Realforce108US Non-contact Electrostatic Capacitance Type Keyboards (White) USB SJ38D0 [Japan Import]?

There are but they are only JIS. So this means you have to get them from Japan and adapt the layout. Or do a transplant and create a hybrid board where you transplant the domes. Actually getting one is going to be the problem. You might get lucky in the classifieds. But otherwise it is likely that you will have to import.
Here is a 108US
If you want to look more into this the 30g boards are all listed on the deskthority wiki look at the table and sort by key weight.
Hope this helps.