Bulova 1966 Chronograph

This is a gold plated chronograph from 1966 with a Valjoux 92 movement. Both the case back and the movement are marked with the M6 date code. I assume the reference #13EB is honestly not readable except for the "13". Like the other mid sixties chronographs on the site, the case numbers and serial numbers don't really match the normal Bulova patterns. Inside the case back there is a stylised 'G" and the "10G" between one set of lugs, again with the stylised "G", it's too small to get a picture. I'm going to guess that G is the case manufacturer? 

This Bulova is definitely my pride and joy of my vintage Bulovas! It is in nice condition, I am going to replace the crystal. It also needs one pusher button because one is kinda worn through on the end. I will probably end up soldering it up because I don't think I'm going to find a replacement. It's either that or trying to find just a button or cap that I can pull off a different pusher. I really don't want to mess with the pushers too much because I don't know if these screw out or push out and I don't want to destroy the pusher tube trying to find out.