Hi Ranger.
Yes sporlan do supply standard drier cases with steel stubs for ammonia up to two inch stubs and the cores as stated do the job.
Check the sporlan supplier, not too many people use them unfortunately.
I inherited a relocated system that was a rush job and liquid ammonia was black with mill scale from pipe work. Started to effect everything in system, every solenoid valve, control valve. Fitted twin parallel filters with bypass valves, gauges and pump out valves, lived there for a week changing cores initially, but now system and ammonia is crystal clear/ normal. No more valve/ control valve issues. Took several cartons of core filters to clean up system. So after clean up now a larger service provider looks after total system and I got tipped out, bugger. They change cores annually only no moisture and oil problems, oil drains normal.