I’ve been using small coated baking racks - the 6"x8.5" ones that fit a toaster oven. When I only have a small amt to sous vide, I make a ‘tent’ out of 2 of them and secure them with silicone coated ties (I get them from Amazon and they’re called gear ties).
These racks (which they said were ‘coated’, so I assumed Teflon type - duh*) have worked really well. The small size lets me use them in a 12 qt Rubbermaid container and if I need to put in another rack to keep the food away from the sides, it’s easy to do.
*Now for the ‘duh’ part: Last week I noticed the cut ends of the rack wires have begun to rust, darn it all. So, I ordered a spray can of Performix Plasti Dip coating that I’m going to try on the racks to see if it keeps them from rusting – I sure HOPE it does because I really like this method of keeping bags upright and away from the sides of the container. The racks are pretty adjustable.
Hmmm - I just thought of something… maybe I should get real LONG gear ties and just make my own holder?? 
