I got it from Ali Express and hope this link works for you. Just look out for the size that fits your current laptop charger. Also check how many watts your laptop charger does, it needs to be able to output 65W if you want to charge a 65W device.
Pro tip: eBay used laptop USB chargers are dirt cheap compared to a GaN charger + USB PD cable. I’ve put laptop chargers all around the house so I always have one available for my laptop, phone and Steam Deck.
Another tip: even if your laptop charger isn’t USB C, you can get a converter to make it a PD USB charger for a couple of £.
Ton of progress?
I would refer to that as “research ongoing but no progress yet”.
Ah, I’ve never tried to convert it that way. Laptops all seem to have had USB charging for many years now.