I have a 1977 Ranger 155A that uses the Chicago Lock Co. 4260-1 T-handle lock that need to be replaced. Do you have suggestions of where I might find these locks. Chicago Lock Co. is no longer in business.

Like these?

T-handle latches at Cabela's

They may not be available anymore. You might want to think about changing them to Perko style locks.  This guy has used bass boat parts at reasonable prices.

http://stores.ebay.com/OZARK-BOAT-PARTS_BOAT-PARTS_W0QQcolZ4QQdirZ1QQfsubZ2QQftidZ2QQtZkm

Like these?

T-handle latches at Cabela's

The ones on the boat are rectangular. I may switch to these as they are less obtrusive.

West Marine probably has what you are looking for, but be prepared to pay through the nose.

I know I found some used perko ones on ebay for 25% of new price.  I would look there.