S2 also made a 7.9 (?), I believe, which had a lifting daggerboard which would also satisfy your draft requirements. It's had success in local PHRF racing as well.
Second Cam's issues with the OMC - they are mostly deadweight or drag on many boats as they have been converted to outboards, and in many cases the cost of modifications results in at least the saildrive leg being left in place. It is possible to remove the powerhead with the boat in the water.