The question of SINPOs is always interesting. In my opinion the SINPO is the best method of telling a station operator just how he is being received. A reading from an S-meter can often tell only part of the story.... if somebody gives a report of S9+20 then the station operator thinks he is doing very well. However, what if that listener has a local noise level of S9+10. That puts a totally different complexion on the matter, which is why I always give SINPO reports as they cover much more than signal strength alone.
And so on to your question. From your recording I would give Batavier 45434. The reading is very similar to yours, but I am a bit more generous with the noise. Maybe my ears just filter it out these days, but I couldn't hear a great deal - more background noise than anything.
A nice recording. You'll have to send some over for the next MW Pirate Review.
I am attaching a recording of Radio Casablanca that I made recently. I wonder what you give this one Dave?