Here is one from Australia
"Bolt-On Kit Wants To Turn Your ICE Car Into A Hybrid From $3,200" October 21, 2023
> The young Australian engineer behind the kit hopes to sell it for just $3,200 and enable buyers to have it installed in a single day
https://www.carscoops.com/2023/10/bolt-on-kit-to-convert-com...
Looks like a backyard operation so far "REVR (Rapid Electric Vehicle Retrofits)"
https://www.jamesdysonaward.org/en-AU/2023/project/revr/
REVR-lutionising the car industry: RMIT student crowned national James Dyson Award winner with electric vehicle retrofit solution 13 September 2023 https://www.dyson.com.au/newsroom/updates/james-dyson-award-...
(Sorry for all the links! but looks like an interesting way to do the conversions!)