Hope this is helpful, my engine is running a KLG FE50 plug. I reckon you could use a CJ8 spark plug.
Not really advisable, as the Lodge CN plug is 1/2" reach, as is the KLG F50 that's in your engine [yep, there is an FE50, but it's 3/4" reach...]. The CJ-8 is 3/8" reach, as is the RJ19LM, so they're too short.
NGK UK's plug cross-reference shows their B5HS as the CN equivalent, and those are easy to find.
