This from ORS4 1126...
3) SERA.5025(a) (IFR - Rules Applicable to IFR flights outside controlled airspace)
a) The Civil Aviation Authority permits, under SERA.5025(a), an aircraft in level flight outside controlled airspace below 3,000 feet above mean sea level and operated in accordance with the instrument flight rules to be flown at a level other than a cruising level appropriate to its magnetic track.
So it seems my worked example is OK. Nothing there about ATC. Just be over 1,000' above anything within 5 NM, just as the OP suggests, and you're good for IMC anywhere in Class G below 3,000'
TOO