Just my humble opinion, but if the pump is suspect and making any kind of expensive noises, pull it all the way down and build it, or send to a reputable shop and have it gone through. They bare cheaper to build when they aren't completely puked...
If you can't afford to do it right the first time, you really can't the second time...

There are not enough moving parts in a Berkeley to say roll with it.
Gaskets, bearings, seals, packing land kit, some grease and an impeller nut can usually get you at least to a point where it won't eat itself... Worst case, a new impeller and a wear ring. At that point, just some paint and it will be like new again...
GT