do it yourself. doesnt take much to do it. I got one of the larger Ms badge too from ebay. Its similar to the e46 M3 size. I thought about it, and decided to keep it stock.
But surely, its easy. I would tape a masking tape at the lower edge of the OEM badge first, before I take it out. Then use a dental floss to pry out the existing, once remove, you would have the masking tape for alignment.
take photos of before and after. I'd like to see it, maybe at BMFeast too since Im coming with the Mid-Atlantic crew