An actual, real deal Magpul lower?
That's what I was thinking!!! There were a very limited run for friend and family. Extremely rare and VERY expensive if you can find one.
If it's just your grips that say Magpul, then it's not the lower. The lower will be identified by the rollmark.
PSA makes a nice, inexpensive complete upper. Bravo Company for one that is a bit higher end. Spike's if you can find one. Lot's of options depending on what your use is going to be.