Don't really want to start filing on the firearm, esp without very detailed instructions, and I'm not sold on the legatilty of modifying a mad. That's why I'm asking about the availability of a proper solution.
There isn't a proper solution, the mag well is too narrow and cannot be replaced. So you need to
1) Modify the mag well. All this might do is void the warranty, but there isn't one, so whatever.
2) Modify your magazines
3) Buy a pile of mags and try them all to see which ones work.
To file the magwell, first you have to remove the magazine catch. You can do this by using pliers to unscrew the button.
Once the magazine catch is out, the bolt hold-open tab and spring will drop out of the middle hole behind the magazine well. It's fragile so it's important to remove it before you start.
Looking at the magwell from the bottom, This is the area you have to widen. Spend about 20 seconds on each side with a handfile, to keep it even, then insert a mag to check for fit. Repeat this process until you can pull the magazine out without undue effort. Don't worry about drop-free, that might remove too much and cause feeding issues. No point in having drop-free mags in this gun anyway.
I've done this with 3 rifles and it's worked every time. Makes them compatible with A LOT more mags.