Looks like a Business strike. I wouldn't know an SMS if it bit me in the behind! Beautiful Toning though.
I recall seeing more SMS examples with toning than business strikes (but that alone is not enough to make a call). Also the SMS tends to be more prooflike but then toning can make that less evident. One more possible thing to look for are scattered small hits. Business strikes are more likely to have them from being handled less carefully than the SMS examples. Making a guess, I would say SMS here ...with some room for doubting my own call
