E whistles are fairly common - a lot of people use them for Scottish tunes in A and most F# minor tunes would fit. I mostly use a D ocarina for the same thing.

Many years ago my mad ex-girlfriend gave me a plastic soprano recorder in B that she'd only been confused by (it's purple with embedded glittery bits). It works as well as any basic plastic descant. I use it mostly for playing along with capo-on-the-fourth-fret singers.

20 or 30 years ago Hopf made a line of Renaissance recorders in just about every pitch. I have them in (baritone) A, alto Eb and E, alto G, descant Eb and E, and sopranino G and Ab (that last one gets me the highest notes I can reach on any wind instrument, since a garklein stops at high G). I missed the D and Bb ones in the EBay auction, annoyed about that.

Another kind of weird-pitch recorder is the German ones from the 20s in A ("sopralto") and D (what in the Baroque was called a voice flute). I have both - the A is nice, the D is crap. They were specified by Hindemith for his "Plöner Musiktag" trio, but it probably hasn't been played that way since WW2. These turn up on EBay reasonably often, mainly in Germany.