hi there
as Ashley has pointed out; hopefully in the near future the plans may be available once again from a new source. If not, and it doesn't work out right; Jim Pottinger drew the plans for the tug FC Sturrock and I know Jim is on Facebook and I have purchased plans directly from him in the past. So if all else fails, or you are in bother trying to get them, maybe try and get in touch with Jim Pottinger directly.
John