That is a Wisconsin engine. It is a WICO mag. Looks like it could be an AKN eng but you'd have to measure the bore to be sure. the tag should be on the front of the shroud.
Looks close to my AK, but could be other models as well, but AK, AKN or similar is my best guess, DougT, correct me if I'm wrong but I don't think the bigger BKNs had WICO's, as all that I have seen have Fairbanks magnetos on them.
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