Look up "Model F Labs." This is their reproduction of a model f buckling spring keyboard. This one has a JIS layout. The colored keys were ordered for unicomp (keys for buckling spring keyboards only fit buckling spring keyboards, not MX type switches).

If you like clicky switches, buckling spring keyboards are great, though you give up a bit of customization. The model F repro is pricy and requires you to be willing to do some problem solving yourself from time to time, but it's definitely my favorite keyboard to type on and it's QMK compatible. If you're new to buckling springs, I'd reccomend looking into a Unicomp keyboard (based on IBM Model Ms) which are less fancy but also cheaper.