“Do you prefer to buy an original piece of furniture or is okay to get a Mid-Century Modern reproduction (knock-off)?”
What would attract you to buying an original but expensive item?
If I buy an original (museum quality piece) of mid century modern furniture it would be an investment as well as a piece of art I really wanted.
It would need to fit my decor perfectly for decades to come. Good thing because, the classic and solid design of Mid Century Modern is something you won’t tire of easily.
The other option is buying “authentic” replicas from MFRs still in business today. (Herman Miller & Knoll Furniture). These newly manufactured pieces are rather expensive but far less than original antiques.
Other option is go with “unauthentic manufacturer”. These can be great finds to compliment your mid mod / contemporary decor.
This takes a little more investigative work, but there are many reputable young manufactures today that capture the zest and style of Mid Century Modern.