To close the loop on my Krale gun order saga, the gun was delivered to me yesterday.
Maybe that little kick in the pants to UPS helped? It was released from Customs the same afternoon I had received the message that the package had been sent to CBP. Hopefully the CBP folks just knew what they were doing and said to UPS "Why are you fools sending this to us, it is just an air gun?"
Unfortunately, and perhaps due to the additional scrutiny (or maybe because I p!ssed UPS off sending them a screen shot of continuous 'Import Scans' with big red "WTF?" letters across its face), they dinged me for customs duties. First time this has happened on an international purchase for me.
Oh well, I still saved money in the end as the gun cost a few hundred $$$s less purchased through Krale even with the higher shipping cost, and the ~4% customs duties were only about half of my local sales tax rate.
The most important thing is that I got my new gun, and that it didn't sit for 6 months in a black hole of CBP.