Welcome Robin, and thanks for joining. The current lowered springs will contribute towards the harsher ride, so returning to standard springs will help improve ride quality. It would be worth entering your VIN into LLL Parts website to obtain the part number for your original springs, and armed with that information, you can then check out prices for quality aftermarket ones. I’ve found Parts in Motion to offer a selection of brands at competitive prices, so worth having a look to their website as well - inputting your registration number. Having said all that, larger than standard wheel sizes will result in lower profile tyres, so check your handbook for what were the normally supplied wheel diameter, Also check whether the tyres maybe XL rated, since these will also be a contributor to harsh suspension. Please let us know how you get on. Regards, Gareth.