Carb trouble

Joined
Oct 18, 2011
Messages
61
89 Johnson 60 hp. So I'm tearin down the carbs, all is goin good. Then on the last carb. The idle mixture scew retainer snaps off. I removed it with an ease out but managed to damage the seat behind it. So now I'm looking for a replacement carb. I can't find this specific carb anywhere. Would a carb from another 3 cyl 60 hp work here. Also what would be the difference between the three carbs top,middle,lower. They look identical
 
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