Movement is hallmarked M6. This Spaceview uses the Germanium PNP transistor, denoted by the 3 wire (red, yellow, green) connecting the coil pair.
In reply to no no i 'm talking about the by Accutronitis
Thanks for the nice comments. The watch is still in my collection and keeping excellent time. Just took the back off to check the ink stamps. The only clearly visible number is the 10/5 which indicates the watch was manufactured in October of 1965. This matches the M5 (1965) date code on rhe case back.
As to the four number code indicating case and crystal number, I am afraid they are almost gone. This often happens when the watch is serviced. The speculation by bobbee as to 5327 or 5377 is a pretty good guess.
http://www.decadecounter.com/accutron/spaceview.htm
though not all inclusive ths database is pretty good...havent been able to locate a 5000 series spaceview at all in my other accutron archives...could it be a conversion?...
The only discernable numbers are 3 and 7. The other two are best guess options, so there is no clear four number code that can be identified as a 5000 series. The watch was purchased on ebay, so a conversion is always a possibility. The case year and movement year match, and as noted in the original post, it has the 3 wire movement configuration. It was during this 1964/65 time period that Bulova was switching to the two wire movement, so this was the last of the breed. BTW, it has the later three solder points and not the early five solder points so it leads me to believe the movement is original to the watch.
There is a "2387", that is the only number i could find that contains a 3 and 7, it's a chapter ring spaceview but it is a straight lug like the one in the ad, the bezel on this watch is a 2548 "Bolt Head Lugs" and as far as i can tell that style bezel was not offered as a spaceview. but i could be wrong. :^)
Also the 2548 "bolt head lug" case was not a chapter ring case so what appears to be a chapter ring is in fact a "coined" dial that has been cut out and install between the movement and the case to look like a real chapter ring which is installed between the case and the crystal......