P-83 and P-85 have the same hole spacing - the throw on the drum now is a P-83. P-87 has two holes like the P-83, but they're closer together than the P-83. So those three holes aren't from a P-87. Also in the blow-up pic you included, it looks to me like it does have snare beds, though it's hard to tell. I thought both throws used similar snare beds, but I can check that since I have one of each snare (both red sparkle) so I'll check to compare beds on the two of them and let you know.
Three point throws were used by Slingerland and Leedy, but the holes in this drum don't look far enough apart to be either of those. And the bottom hole was the same size as the top two (and not enormous like in this picture). I believe some really old Ludwigs used a three-point throw similar to the Slingerland, but it was long before this snare was made.
So my guess is there are two possibilities: 1. that the drum originally had a P-83, but it was taken off and replaced with some weird Japanese 3-point throw (see the "Appolo snare throwoff" thread - it may be that throw) until someone found an original throw and put it back on; 2. that the drum is actually cut down from a marching snare and repainted inside. That would explain the non-standard bearing edge and too new looking paint, and would also explain the large hole under the throw which could have been for an original vent.
If its the first possibility, then it is probably worth buying if you need it and can get it for a good price.
If it is the second (which is actually my guess - you could tell for sure by looking at the interior paint, the bearing edges and snare beds, and the vent grommet), then you would be better off staying away.
