Thanks for your input Albert, I’ve been scratching my head over this for a a while and any references and photos that can help are appreciated. I’m still not fully committed one way or the other. The kit has Imperial Russian markings, but as I understand all RNAS vehicles sent over there had them applied. As for my decision on the armament, it’s based on the few photos I have found. From what I can tell they do seem to have a Maxim going by the smaller muzzle with no flash suppressor and deeper breech. The bottom of the breech on a Vickers is more or less in line with the cooling jacket. The Maxim and MG08 were much deeper as can be seen in the second photo. Can sometimes be hard to see that from certain angles, but I think that shot gives it away. The charging handle is also a little different when compared with this Vickers and the Maxim in the photo with the Russian troops.
I did find this article a while back by Bryan Perret who states they were armed with Maxims, but gives no reason why or a source. I’m also bearing in mind that the article was originally in a 1979 issue of Airfix Magazine, so references were probably even fewer than now!
It’s a bit of a gamble on my part I admit and I am basing it on the few photos I have found comparing against a Vickers. Best I can do given what I have found. If it turns out to be wrong, at least it’s something that can be fixed quickly if new evidence turns up. It’s more than likely that they could have originally arrived in Russia with a Vickers, but lack of supply of .303 resulted in refitting with a Maxim at a later date. It’s also possible the Russians could have repaired them when the RNAS left and put them back into service.
Now, what tripod the thing was mounted on is another question entirely!