The PoolTrends CM12 (which has horrible reviews) is on the mothership, with Prime, for $8.
I didn’t check them all - but many of the chemicals can be had for less at your local Leslie Pools - where they will test your water for free and TELL you what you really need. And the shock there is 73% active (as opposed to 68% - which is still better than the 35% crap they shill at WalMart)
The T.K.O. Shock Treatment featured in this event is a 73% active shock. Leslie’s Power Powder Pool Shock (their 73% shock) is listed on-line at $99.99 for a 24 pack, and $55.99 for a 12 pack. The 24 pack here is $78.99 ($20 CHEAPER!!!) and the 12 pack is $47.99 ($8 CHEAPER!!!).