Get pkgin binary package pkgsrc version

[Julien Savard <juliensavard17%gmail.com@localhost>]

Hi,

I'm using pkgin on my old SparcStation 5 running NetBSD 9.1 sparc. I'd like to install "moc" however it's not available on the pkgin repository here :

https://cdn.netbsd.org/pub/pkgsrc/packages/NetBSD/sparc/9.1/All/

I'd like to setup my own "supplementary" repository for packages that are not available but I want to make sure it's compatible with the official packages available by NetBSD. 

According to the directory date I can see here https://cdn.netbsd.org/pub/pkgsrc/packages/NetBSD/sparc/ 

I'm guessing it's pkgsrc2020Q3.

So... is there a better way to know on which pkgsrc version (2020Q3, 2020Q4, etc) a pkgin binary package has been built?