Someone else has successfully replaced this plug with an NGK BPMR6F in an SV-26 engine used in an r/c plane.
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,
Champion J19LM
Bkr7e
Z9y
yes
Bpr7es
Champion RN4C
There is no Champion spark plug with the part number 696798. There is a Briggs and Stratton part number 696798 that does cross reference with a Champion RJ 19LM.
Champion RJ19LM
Champion rj19lm
Champion Spark Plug QC12YC
Rc12yc