There's cards out there, but based on what the card is actually doing, there are always going to be "issues," especially depending on what you're trying to accomplish, and the associated hardware.
Did you see
this card and
this card?
You didn't mention your goal with a usb 3.0 adapter on an "old" macbook, but you may want to ask yourself if the trouble of one of these cards actually makes sense. If there's a binary purpose, i.e. a special USB 3.0 drive that you must absolutely connect to your notebook (because there's absolutely no other way to get the data to your notebook), then you obviously have to go for it. If you're trying to achieve a better level of data transfer performance or connectivity, I'd say it's doubtful. In summary, I don't see the USB 3.0 expresscard being ideal in much of any sense.