I replied to your message and sent you an email. :)

I checked my stock and I have (2) of the stop locks like the one Al Percival recommended. Send me a PM is you want them. :)

I believe the ones I'm referring to are used on the arms of boom stands (and not on the base of the stand). I wish I knew the part number. Maybe you could call Pearl and see if they know which...

Pearl does have some 5/8" stop locks. Perhaps you could try one to see if it works.

Great idea!