I'm similar but not to your degree. I wore a small v08 as well but medium in everything else (never wore 4500 bc it didn't fit my head shape at all).
My experience with the 910, tacks x, and 720 were similar too. Where small at largest was too tight and medium at smallest was a touch too big. Although the tacks x and 910 felt like it could work depending how long my hair was lol.
What had worked for me well were these:
- warrior alpha one pro. It uses a boa dial to adjust like a bike helmet.
- CCM 310/710 it has an occipital adjustment and isn't just forward and back like the tacks x, 910 and 720.
- 920. Unlike you, this actually worked for me, but I am at the smallest setting. Initially I thought this wouldn't work but realized I could actually make the medium go smaller with a bit more effort pushing the sides of the helmets together. Right now the setting has 2 vertical lines on each side of the locking tab. Just nonchalantly pushing the shell together and stopping with the first sign of resistance, the sizing was at around 3-4 lines on each side of the locking tab. Hope that makes sense but if you look at the rear of the helmet where the locking tab is, it'll make sense.
Imo the 310 should work for you unless your head size is smaller than a 7 hat size. I'm 7 1/8 hat size so medium in the 310 fits me well near the middle to smallest setting. the smallest end of the size range for the 310 is 6 7/8". So I would assume the 310 is your best bet if the 920 doesn't work on the smallest setting. What's weird about the sizing is that the 920 is actually advertised as a starting size of 6 3/4 for medium, which is smaller than the 310, but I can confirm that the 310 definitely fits tighter.
You should also try the Bauer reakt 85 and up as they have good adjustability.
ive attached a picture of the back of the 920 where it has the vertical lines by the locking tab that I talked about