While a longitudinal front engine and rear wheel drive was once the normal configuration for most vehicles (to the point that is sometimes referred to as the "conventional" layout), it is now typically used only for
- large cars
- luxury vehicles
- sports cars
- high-powered cars
- trucks and larger commercial vehicles
Sports cars often have the desired layout, but are typically neither cheap nor easy to pile a bunch of battery into. Yes, a few people in this forum have jammed sufficient battery cells into a tiny Triumph Spitfire to make it work, but with some "interesting" battery packaging. There are some Mazda Miata/MX-5 conversions, too, and that's a very small volume of car. This type of vehicle may have very restricted engine space length; for instance, the current MX-5 and Mazda 3 compact car use the same engine and have the same length available to hold it - the longitudinal layout doesn't provide any benefit.
The easiest choice here in Canada would probably a compact pickup truck. There is engine space, the separate (from the body) frame is easy to work with for motor and battery mounting, and battery packs can be mounted under the cargo box. Although there are none sold here now (the smallest trucks are now much larger than they were), there are still examples of the Ford Ranger, older Chevrolet Colorado, and early Toyota Tacoma available. I don't know what sizes and ages of the equivalent Ford/Mazda, Toyota, and Nissan trucks are readily available in the UK. My guess is that they might be less common there than here.
Although this car illustrates the challenge with engine size it also demonstrates that the problem is manageable: it is VW Polo Mk2... a car so small that VW never sold it in North America.
One issue with the longitudinal engine and rear drive layout is that the driveshaft breaks up potential battery locations; it's easier to wrap a fuel tank around a shaft than to package fixed-size cells around one. On the other hand, front wheel drive EVs tend to end up with a pile of battery in the back, and so are bizarrely rear-heavy for a front-drive vehicle.
I realize that none of that provides any answers, but I hope it provides some food for thought.