You are very close
, indeed!
But this is a Pratt & Whitney R-1340 engine not a R-1535
. You need to go back a few more years in time.
So you have identified:
1) that the looks are of an American plane
2) but not in American service - look at the tail insignia, the uniforms (or what can be seen of them) and the general "atmosphere" of the picture - a kind of nonchalant attitude of the pilots in front of this difficult to explain (and maybe to achieve) damage of the upper wing leading edge - the one on the left seems posing for a "
photo souvenir".
3) and the engine is a Pratt & Whitney R-1340 Wasp
Now, remember what I said about the common points with the Bellanca 28-90 "Flash".
...and about strange birds in these skies