Well after 4 months of no news on the Eduard-Brassin 10,5cm gun, I sent in another support ticket (see below).
I would invite others to join the campaign in asking Eduard for an update on the course of action & timeline for a corrected version.
Otherwise, I fear that nothing will get done.
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Hello Libor,
It has been many many months since this issue was first reported, and 4 months since we last inquired about it. To date, we have heard nothing further about the resolution of this issue.
The gun that was produced was a wonderful piece of work, but the mistake in the scale is much too big to overlook. We are eager for a new, correctly-scaled version!
May we please have a firm update about what actions have been taken to resolve this issue, and the expected timeline for the release of the corrected product.
Please do not simply give us a cursory reply that the matter has been reported to Brassin... and that is it. We deserve more than that.
Respectfully,
Glenn Cauley
(on behalf of many in the model submarine community)
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Oh Dan Dan Dan... you have NO idea how disappointed I was to find out the Eduard gun was waaaayyyy too big. The detail on it is simply beautiful. 
I had thought of the same thing as you... to kitbash. Unfortunately, since the Eduard gun is roughly 22% too big, I doubt there are any parts that are useful to use on the RCSubs gun.
On another note, I heard back from Eduard support:
"Thanks for letting us know about this issue and for elaborating the details for us.
I've already passed your message to our Brassin development department. Our guys will look into this and decide, whether or not there's a mistake to fix.
If we want/need your further support, we'll get in touch with you.
Thanks again for your support!
Libor Havranek"
Uhmmmm...... I am not sure I like the choice of words....... "whether or not there's a mistake to fix."
There IS a mistake... a "22% too big" mistake...
I hope that they take responsibility for the error, so that they can move on and re-issue the kit, properly sized.
Again, I am calling on the good people here (who know their stuff) to lodge a complaint with Eduard... so they don't think I'm just some lone crackpot whistleblower type. 
