I found this site with relatively cheap expanders: https://www.bracesshop.com/en/palatal-expanders/
They send you an impression kit that you'll send back so that product will fit your palate.
Since the DNA and Homeoblock seem to quite effective I thought "Why not just get one of these?". They're cheaper and when they don't fit anymore you can just order a new one. There's even one with fancy springs of the Homeoblock and DNA appliance.
What do you guys think about these products? With you current knowledge is there anything that looks wrong/great?
The "Stretching Plate with Cheek Guards" looks the most similar to the Homeoblock/DNA so I'm guessing that would be your best bet if you're going to buy one.