This is what you need to do the repair.
http://www.ebay.com/itm/Champ-Choke-...hW1oa6&vxp=mtr
If you have a original carburetor it is probably the Autolite 2100 but it doesn't really matter as the manual choke works the same on most of them.
You should check the choke enclosure before you hook everything up, there should be a slight vacuum in there to pull the manifold heat up from the manifold.
If there is no vacuum you should clean the carburetor to open that vacuum port, if you don't do this it will take a lot longer for the heat of the manifold to reach the spring and open the choke.
Exhaust gas does not go into the tube only heat, if for some reason exhaust gas comes out of the hole on the manifold that you plan on using DO NOT USE IT as this will only work for a short while before damage is done.

They do make electric chock kits, they are getting hard to find and are expensive & you need to know what your carburetor is to get the right size unit.