Purchase for $15.00 each on Amazon:

 https://www.amazon.com/dp/B01F5REBUM 

 

Walmart.com:

https://www.walmart.com/ip/OPSol-Mini-Clip-for-use-of-12-ga-1-75-shells/701712239#about-item

 

The Ammunition Fairy:

http://www.ammunitionfairy.com/Mini-Clip-12-gauge-Minishell-adapter-Mossberg-500-p/miniclip-minishell-mossberg.htm

 

In Lubbock, TX get your OPSol Mini-Clip at:

LSG Tactical Arms, 2650 34th St (34th and Boston, Northeast side)  Ask for Steve.

 

And many other fine gun shops across the USA including but not limited to:

Gold Mine Pawn Shop

http://goldminepawnshop.com/