Re: cymbal stand repair (clamp)
I have some Pearl 900 stands as well. Not seeing what it is that is broken in yours I have to just improvise a few solutions.
I am also not sure if Pearl sells all the parts on their equipment, but if they do you may want to contact them for the replacement parts.
You could also try to take out the plastic part and try and glue it together for repair.
You could re-manufacture the plastic part that is broken. Just to be certain there is a slot there in the plastic and I am assuming you already know that and are not confusing the slot with the plastic being cracked. I have not taken the plastic out my own base tube, but it appears to be just a plastic tube with a flange and a slot that fits into the base. This can be replaced by another material if you need to like a brass.
If you go to a machine shop take the part there and see if they can repair it or replace it. The part does not necessarily need to be plastic, it could be made of a brass that can be easier to machine especially if the part is small, and from my experience, even if the machinist is very skilled, they sometimes have a problem with plastic. The machine shop option can be expensive though, it all depends on the labor costs in your area and whether the machinist takes pity on you.
Another option is to purchase a used 900 stand on ebay or craigslist and find one that can be salvaged for parts.
I am not here just to keep the beat; I add color, timbre, and presence.