I just bought a small electric motor on ebay whose seller was in Ontario. Didn't seem to be any problem crossing the border other than the shipping was more expensive than a comparable distance when both point of origin and destination are in the same country.
I would email them and ask. It's original purpose is as a blasting abrasive, so I doubt it's on the State Dept. list of restricted items. Just calculate how big your tumbler will be and figure 5lbs. of media per gallon of water. Too little media doesn't clean well.
The two fine folks there that answer the phone are Kathy, and Kevin Walters. Kathy can take care of your ordering needs. If you have technical questions, ask for Kevin.
kwalters@pelletsllc.com
Point of clarification. The pictured tumbler was what he used with corncob. I would be hesitant to fill it full of water and trust it not to break. But a metal 5 gal. bucket should work.
I have read conflicting reports on using a small cement mixer. One fellow had good luck with his, another said the cases sit on the pin bed and don't clean very well. So it's probably a matter of tinkering with it, angle, speed etc., to get it to work well.