I don't play keyboard, so I have only second-hand info, but my acquaintance tell me that most of the major builders do offer "piano feel" keyboards - probably for a little extra $$$$. I'm told that they can be almost indistinguishable from the real thing.

I don't know whether these keyboards are available in "portables," but they seem to be an option on the big'uns. My impression was, a few months ago, that you have to look for the feature, as it's not too much advertised.

An intermediate approach, using just "weighted keys" was not much liked by those I've talked to, with the exception of a couple of church organists I met briefly.

John