So with only 50k copies made in 43, where did they all go? Did they all likely see action? I wonder how many actually survived. Anyone know good information sources for this?

I read all of them saw service. The one I own and the three others I've seen look it too.

I'd say quite a few of the 50k survived. They were not totally uncommon to find them in the imports I have 4 or 5 of them myself.

I think there is more than 50,000 of them.  They don't seem *that* rare.

The 50K figure has been out there for quite a while on several boards. Back in 2005 or 2006 there was a batch of them that were imported into the U.S. I had 4 of them at one time, but sold three of them off to other collectors. It may seem like they are everywhere, but most guys on the gun boards are collectors so most have one, or two.
I can't recall ever seeing a 1943 in any of the batches of M44's our LGS used to get. I did snag a 91/59 out of a batch of M38's and a 1944 Tula M44 from Big-5, once upon a time, in a Galaxy far far away.

Many have survived and there are even examples of Finn captured ones. I need a 1943 45 and 46 to finish off my russian M44 examples.  If you have an interest in these, you really need to visit the Gunboards forums mosin nagant thread.

Well -- one of them lives in Ohio  

I read "somewhere" a couple of years ago that it was estimated that half of them survived the war.  

The war was pretty ruff in late '43 thru early '45.  These new carbines would have went to the front lines.  I would say that half of them survived.

Just my 2 cents  . . . .

The 50k production volume is probably severally understated one. 1943 M44s are quite commonly encountered, considerably more so than say 1940 or 1941 Izhevsk m91/30 or even 1939 M38