Atrend 10LSVDD Digital Designs 10” Single Vented SPL Subwoofer Enclosure fits 500, 1000, 1500, 2500 (type 1) and 3500 Series, black (FBA_10LSVDD)

Anything that is 1 ohm will work. But of course you want something that will be louder than an Infinite Baffle 8. I used an Atrend 12" ported box meant for a DD. They don't sell it anymore on Amazon. https://www.amazon.com/dp/B00OVD1TX4 and ID12 dual 2ohm sub https://imagedynamicsusa.net/us/en/products/subwoofers/ID12D2-V4-1-1/ I picked this sub because it has the highest sensitivity I could find and was low priced and since the power numbers are not published for the Bose amp I figured it was very low. So this 250 rms fit the bill. And ID is an SQ driver. Stuff like Skar and most cheap subs will have very low sensitivity thus won't get as loud.