Perhaps I'm missing their long and storied history, but I have a feeling that the "Best Of" here is by default, and that they're playing a joke like the Crazy Aces' Greatest Hits Volume 2 (their first album).
While my internet detective case didn't come up with anything confirming that, I have a bit of a hunch outside of that. You see, the Okay-Men bear a pretty strong musical resemblance to Stronzo Gelantino and the Boo-Men. Polka-influenced beat, very similar guitar tone and production. Even the names Boo-Men and Okay-Men sound a bit similar, and their art shares a similar color scheme of red white and black. AND both groups are from Cologne, Germany. AND Stronzo Gelantino and the Boo-Men's sole friend on Reverbnation is, you guessed it, the Okay-Men.
Now, they're both surf groups in the same city, it's very likely that they're friends. And I went as far to do WHOIS lookups on their websites: different names, so no definitive proof. Sure, it would be best to just ask, but I'm having fun here.
ANYWAY, I'm pretty happy with anything that sounds similar to the Boo-men so whether I'm right or wrong this is a win for everybody. In addition to a download on bandcamp, you can order a 7".
Case closed, boys. Contact information for Stronzo Gelantino goes to Gary Grutzek. The very same name I sent my paypal money to when I purchased this.