See the ad below from Hot Hemi Heads website

Date_of_Posting: 02/11/12
Name: Larry Thomsen
Part_Title: Push Button Units
State: CA
Country: USA
Email_Address:
thomsenclayworks@charter.net
Description
Click photos to enlarge.
NOS 3 speed push button shifters with pod for small block 727. 1961-64 rare find in orig. wrapping. Perfect for our Hemis. I have photos. $300