I have an Old Sekine 10 speed that belonged to my dad and I would like to put some new derailers and brakes on it.

My question is right now it has a Shimano lark rear derailer and a thunderbird front derailer with down tube shimano fingertip shifters. Is there a current set of derailers that will work on this bike or would I also have to change the cassette and crank as well?

Second it has Shimano tourney center pull brakes. They are in pretty good shape and work OK, but I need to replace the levers. Are there current shimano levers I can use with this type of brake?

Any help would be greatly appreciated.

JB