Hey now,
I've researched these mics a little. They are the same as the marshall mxl 1006 series. The SP2 is the equivalent of the mxl 1006bp and the SP1 is the equivalent of the mxl 1006. There aren't too many around anymore (new), so I would try to get the newer version mxl 1006 mic if I were you. They can also be found for around $50/each. Many reviews are very good for these mics, and say that they are definitely the best LD mics in that price range. I think a member here called VA Taper uses / used to use these mics and could give you a mp3 link perhaps.