Another comparison might be a Jeep Wrangler base 4dr (4449 lbs curb weight and up) compared to the 4xe PHEV version (21 miles of ev range, 5,072 lbs curb weight and up). Roughly a 500lb weight increase.
You could try this comparison on 2wd vehicles as well if desired (e.g. toyota prius vs. prius prime).
While neither scenarios are an EREV, the comparison is a bit similar in thinking about the tradeoffs in hybrid conversions of existing ICE vehicles, where presumably the engine would be retained and drivetrain/battery components to facilitate electric propulsion are added.
Designing an EREV from ground up can be much less weight but depends on vehicle type size, such as a BMW I3 (a small urban 2WD car with CFRP body panels, narrower staggered wheels and other weight savings by design) has a curb weight closer to 3276 lbs. There's tradeoffs with that low weight - the small range extender engine has less power, the gas tank only adds about 80 miles of range, etc.