Fix the one you've got. A squeal is just a lack of lubrication. Take it out, remove the vacuum advance, and soak the whole distributor in a container of solvent like mineral spirits or Diesel fuel for a few hours, and give it a good inspection. The only reason to replace it would be severe damage or extreme wear.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!