The simplest solution is going to be a Roland SP404SX
because it uses cheap SD cards for more hours of storage than you could ever use and it works with WAV files, no conversion to a special format is required....just copy them to the card on your computer, put the card into the 404 and you're done.
You can trigger samples from tapping on large pads or over MIDI (from a keyboard, footswitches, you name it).
It's available in music stores all over the world so you'll have no trouble finding one.
There's a reason everyone is telling you to buy a 404
I listened to Hatfield and the North at Rainbow. They were very wonderful and they made my heart a prisoner.