I hope y'all will excuse me for drifting back on to topic, but I picked up a No4 Mk2 at Marlboro today.
The S/N is PF323, which might be an importer's number, or maybe from rearsenalling, but it matches on the receiver and bolt. Bluing is very good 90+ on a guess. Action is smooth and clean. The wood is VG, I'd say. Again all of this is based on my novice level as a collector. Much, much, better than the "Collector's Grade" piece I received a week ago. Which is going back, but I digress.
Back to the rifle. It has the adjustable rear sights, not just the two position peep site. I did Milsurps 4 Me's "bullet test" and the bore seems tight. I haven't been able to shine a light down the barrel, because that would only get the light greasy. However, based on the amount of Cosmoline, I'd guess there is NO rust down there. In fact, the only rust I noticed was a bit of surface rust on the magazine.
Not only is it covered with Cosmoline, but it's been in storage long enough that dust has stuck onto it. Kind of makes it look like it's been tarred and feathered. <G>
This will be another several night cleaning project, but I expect the result to be satisfactory.
Gary