Can't give you a direct advice, but here's a warning in general. Recently I have discussed with friends options for
my buddyseat and one had this warning I'd like to pass on.
The seat on my model, the CB500K2-ED differs from the seats on previous CB500 models like the CB500K2-A.
My seat,
PN: 77200-374-003, is also on the:
CB550A MOTORCYCLE, JPN, VIN# CB550K-1000001
CB550K1A MOTORCYCLE, JPN, VIN# CB550K-1200001
CB550KA (76) 550 FOUR, JPN, VIN# CB550K-1230001The thing is that unlike
previous models, that thin imitation chrome strip is
vulcanised to the vinyl of the seat. This makes replacing the cover a bit difficult. Aftermarket products often are not 100% true for a specific model, but generic. Although I usually ride with a removable sheepskin (very comfy on long hauls, warm in winter, cool in summer and guaranteed no hemorrhoids

), I still consider restoration of my seat for the looks. In Holland we have specialists who can do this and - more important - they have knowledge of the differences in CB models. So that will my route. I don't know the characteristics of
your seat and if the original looks matter or not.