No its about 50 all up, the thread on those is 1/4 NPT I made up a spunding valve manifold in high pressure plastic pipe thinking at the time it would be a good idea. In reality it cannot work unless all beers to be fermented start at the same time.
But still a good idea to make one up to control the venting of one vessel.
I went and bought a 1/4 NPT tap, being I was only using it on plastic no damage to the tap cleaned it up and took it back saying I had fucked up it was a 1/4 BSP tap and I already have one so got my money back
I’d question the need for an adaptor, I’ve screwed one of these directly into a bsp brass female tee piece with no issues. If we were talking high pressure then an adaptor would be needed but at 30 psi max no issues.
I think my partner has a shipito account, perhaps we can utilize that and get a bunch from the US for cheap?
On Amazon it's US$11.14, but comes to AU$48 posted, pretty much the same as eBay Australia.
Or, try convince KegLand to stock them?