Welcome to 'Club Heuer' Steve.
Really nice GMT ! Bezel seems to be in fantastic order. Those silver face Autavia's you mentioned come up reasonably regularly on ebay & through this sales forum so you should easily be able to track one down.
Good hunting - Darren

: Hopefully I have finally and successfully, added a picture of my
: Heuer Manual GMT that I purchased in late April. This was a one
: owner watch, purchased from the estate (via e-bay) of a pilot
: who participated in the predecessor to the Powder Puff Derby's
: with her sister. The watch keeps very good time and is my first
: vintage Heuer. I also own a few Breitlings which I'll post
: another time. I have the Heuer bug now, and hope to acquire a
: silver dialed Autavia automatic with orange hands and subdial
: highlights (the "poor man's Siffert").