Holy Moly you got those chambers packed to the gills!
I'm going to second guess your hesitance to make your own chamber, only to suggest you reconsider other options. Buying a quality (perhaps used) commercial 'fridge and making your own curing chamber seems much less dicey than buying an semi-expensive and untested unit from some potentially questionable business on the West Coast (that doesn't have any commercial listings other than eBay), and just hoping that it will all turn out well gives me a bit of a pucker factor just thinking about it - but that's just me.
The Sausage Maker unit looks nice, but when I look at the amount of product you currently have hanging, I think it will be inadequate for your needs.
Here's a vid posted by a professional chef working in a commercial kitchen/restaurant who makes a nice curing chamber that in my mind is as good as, if not better than, the spendy units found online. If something goes wrong with it, a refrigerator repairman can fix the 'fridge, or if it is a controller or humidifier/dehumidifier problem, you just replace it with minimal cost. It doesn't look quite as professional as a dedicated curing chamber, but in the end, it does exactly the same thing for a lot less money.