Not to sound like a broken broken broken broken broken *smack* record, but you can get a Motion Marine jet boat as small as 18', and they will seat 4 people easily. You can even configure a boat online and get a quote from there.

I've ridden in one recently and they're a great boat. Give Mark a call and he'll take ya out for a spin.
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Get Bent Tackle whōre. Just added spinner section, where you can special order to your hearts content!