Tub drain gasket needed?

Hi,
I will be reusing the piping for the tub drain. The old tub squished a gasket between the pipe and the bottom of the tub. Is this still needed or can Teflon tape and plumbers putty be used?
Also with the overflow there was a Moen gasket that slipped over the flat part of the pipe(the part the drain face plate screws into) and then the sleeve part of the gasket got pushed into the tub. Is there an alternate way to seal an overflow pipe or should I try to find a replacement gasket?

Thank you

 

Those gaskets are sold even at Ace harware stores packaged and labeled for that purpose.