I'm pretty sure Scalextric haven't released any individual digital cars for very many years. Jadlams sell new DPR cars in which they've installed a chip and list them as 'digital' on their site. I know other retailers will fit the chip into a DPR car and some even offer a c7005 chip-fitting service for non-DPR cars. But you will always pay the cost of the car + the cost of the chip - and in some cases (especially where soldering is required) an extra fitting fee.
It's extremely easy to fit the C8515 and, if you shop around and use discount codes, you can get cars for a lot less than £41 and chips for as little as £13. The 10% discount for Scalextric Club members on this site (plus free postage on orders over £30) is certainly useful.
Of course, there are eBay sellers who sell digital cars split from sets, some marked 'new' and some 'pre-owned', mostly older super-resistant GT cars.
I understand and agree with your comments.
I am quite happy to fit plugs myself but struggle to justify buying seperate car/plug when it costs me more than a supplier will sell ready fitted.
You mentioned Jadlam so you will know that they sell new high detail cars fitted with C8515 at a discounted price. I was just asking if anyone knew/used another supplier. (For my needs I would save £40)
For my own reasons I would prefer not to buy from Jadlam.
Unfortunately new people cannot join the 'Scalextric Club' and enjoy a discount.