AND it shows how Gamera "transforms" into the flying pose.

Showa Gamera IS bigger than the first Heisei release. Here is the side by side comparison. Not a huge monster in size, but definitely bigger figure. Link:
Look at the very bottom of the page, at where it shows Japanese writing and the year 1967 and Coming soon. There are 2 "coming soons sections there. Can anyone translate the name of those two things to see if one is Gyaos and see what the other one says? It could be the next "monster".