The armature on a Skill Saw Model 574 7&1/4” started sparking slightly more than usual. Then the armature developed a dead spot. Bummer…Brushes are fine…Only about half worn down and freely pushed by the springs.

(1)Does anybody stock parts for these older saws?
(2)Does anybody maintain an old-tool junkyard for the sake of scrounging unavailable replacement parts?
(3)Can armatures for any later models be retrofitted?

Help!…Thanks.