Originally Posted by Bassem
If you're not comfortable trying the repair yourself, take it by a local plumbing shop, and ask them to sillfoss, or silver solder, the leaks. You may have to leave it there a day, but it should only cost $25 to $40, and they'll do it right. Or hit craigslist and call one of the plumbers that adv there, they are usually very inexpensive.
Good luck, my friend!
i really think you would end up with a fixed stem that had solder spots still on it. also silver solder WILL cause copper plating, which you wont get off unless you have a)super pickle (jewelers pickle 50/50 mix with H2O2), or b)abrasives
also it is not the best thing to silver solder (braze) a piece of brass (and pretty much any other non ferrous metal except gold) with out evenly heating it up to annealing temperature (or there about), and on a piece that big it will be impossible... not to mention that it would melt out all the other solder joints in the piece since it is low temp solder. if there is low temp solder on the piece that is heated to annealing temp of the brass it probably will fuse to the brass and can eat the brass away