Gents: One more Opinion on the nature of that Flak mount:
I think the kit and its instructions do include the mount turn-table base. And lots of good argument has been made above in terms of the whole mount being available at that field shop, so why not put the whole thing on as versus cobbling a partial mount... - Which sounds completely reasonable to me!
But, just for some "what-if" fun... Here's a wacky idea!
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First, let's admit we DON'T KNOW their actual intent for this vehicle - we ARE assuming that the Germans were thinking of using this as a FLAK gun or tank... (Not that I am saying in any way that anyone is wrong in this!
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) So... Bear with (laugh OL, but gently!), please: The Germans had a long track-record of creating "assault guns" by lashing weapons onto any vehicle - with rather limited or even "nil" traverse. I offer for your amusement the thought that maybe the Germans created this thing as a sort of urban assault vehicle!
It is well-known that they used flak guns as infantry fire-support against ground targets- and the T-34 chassis was substantially agile enough for this to be effective in the "let's swamp those guys in a storm of lead (steel)" approach where a gun could be trotted up and used as a fire-hose against a building or emplacement. Precision aiming wouldn't be required in this suppression mode...
That silliness offered...
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That gap between the gun armour and the hull... Certes, if YOU were doing a field lash-on of this, wouldn't you find it a heck of a lot easier - and MUCH more stable (more robust weld-on), to simply "park" the add-on armour like a fixed casement on that hull? IF that mount was intended to be "fixed", I can see NO good reason for not doing this. I take that gap to be a pretty compelling argument for a traversable mount.
I would suggest also that pics taken of vehicles on road- such as forming up for or in convoy, etc., will almost always show guns trained fore-and-aft. It's been the way of armies around the world to travel thusly. (Putting aside those cases where a convoy flak vehicle MIGHT be trained out toward a presumed likely attacker... of course, predicting the direction enemy planes may actually attack from is fraught with risk...!
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). Likewise for "shop", depot and factory yard pics. One could as reasonably argue from these pics that typical tanks actually came with fixed guns!
As to where you might buy that kit...
If you don't find it on any e-shelf at Squadron, SprueBro's, HobbyBuy, etc. (but there are many more e-sites to visit...), there is always EVILBAY! That, and I have seen at least one of these at each of the past 6 model shows I've been at... They are out there!
PS: This-all has peaked my interest in this one, too, so I'll be looking to spend more money I really shouldn't!
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It could be a really cool build!