I just bought new carb clamps for both of my bikes. It is easy to find stainless band clamps that are long enough but the ones I could find locally are all 1/2" wide where the originals are 8 or 9 mm wide and have to fit in grooves in the rubber that are about 10mm wide. Honda specifies different sizes for the CX's inlet & outlet and for the GoldWing but they are all between 55 and 59mm (can't remember which is which off hand, which is why I mentioned the CX).
Someone on cx500forum.com found Norma Torro (also known as Awab Torro) clamps that are 9mm wide.
You want part #NT09060-W4 (40-60mm). They should be less than $2 each. I found them at this site but if you aren't in Canada you should probably look for them at a marine supplier closer to home.
I have installed them on the 650 and they look way better than the originals.