UK spark plug cross reference information can be found on the instructions when purchasing a cross spark plug that works in the UK, or on websites that provide information on cross spark plugs.
i found it on ngk #2238
I found it in Champion spark plugs as "RCJ8Y"
The laser 40500 Champion cross reference is for spark plugs. There are many cross reference data bases to show which spark plugs can be interchangeable.
Most all brand spark plug brands are on the cross reference including Champion. Some of the brands that cross reference to Champion are Autolite and Denso,
Many spark plugs can be interchangeable if they fit the motor in question. To find out which can cross reference with the Laser 40500, a cross reference catalog should be referenced.
Try NKG TR5 (2238). I found it on the NKG website
Bpr6es
802592
Ngk bpr5es
Champion Spark Plug QC12YC
Champion RJ19LM
Champion rj19lm