why bother with high costs of a decent cam without having any advantages over what you have. Also newman, kent, piper etc don't make hydraulic lifters. Where do you think they come from?

Even an off the shelf mild road cam would be fine if you wanted to stick around standard power. By the time you dialled it in and set the cam properly with std parts you probly wouldn't see much gain anyway maybe a few bhp but still drive the same.

Why not get a slightly larger intercooler paint it black so you don't notice it. Fit a chip if it doesn't have one and then the mild cam will make it a bit more lively and still look stock under the bonnet.