Sure I remember them, and they are still trading. The AE APEX oil rings were a very similar to the Cord three part ring, might even have been supplied by them raw and repacked in AE Livery.
Way back Dad had an ex Hanger Motors (Birmingham UK) FordE93A Van, the old sit up and beg type with a longstroke side valve engine, well known in motoring circles as a natural burner even from new. Times were tough, and this wreck used as much oil as petrol. Father saw an advert in the paper, and as an ex RAF engine fitter had no problem fitting a set, which true to the advertising puff transformed it into a reliable runner and it was used as a stop gap for several years. He traded it for a Morris Oxford series MO, leather seats, 4 speed box AND a heater. Yes folks, that's how it used to be in the 1950's.....heaters were an optional extra!
Used Cord rings myself on a selection of ex fleet cars of the 1980's, Cavaliers, Cortina, Sierra, Crossflow and CVH Fords. The rings would seal at the first turn of the key, the secret being to use cheapo Supermarket Oil with non of the anti wear additives as a first fill. As well as a good radial pressure against the bore, the dished feature on compression rings compensated to a degree for worn piston ring grooves, often overlooked when re using old pistons, any up and down movement of the rings in the grooves will pump oil up into the combustion chamber. The back to back spring loaded individual parts of the ring compensated for this wear.
Sparing no expense on oil with your new A10 Bore and Pistons could be why some rings don't seal, the anti wear lubricating properties of all singing and dancing modern oils are just too good for traditional metallurgy.
Swarfy.