<p>I play a <a href="https://en.m.wikipedia.org/wiki/Berimbau" rel="noreferrer">berimbau</a> for Capoeira. One of the most fragile (and most expensive) bits is the <em>cabaça</em>, a hollow gourd used as a resonator.</p>

<p><img src="https://i.stack.imgur.com/tRNcL.jpg" alt="cabaças"></p>

<p>I'm not very familiar with the qualities of the resin used for 3d printing. If I were to take this to our local Maker Lab and have them scan and print a copy, how likely is it that it would work? My fear is that the plastic would be too sound deadening.</p>

<p>If you want a less exotic parallel, imagine the body of a guitar. That's a resonating chamber.</p>

I'll take a stab here, but my gut instinct is to say that a printed part will not sound the same as your original gourd resonator.
I believe the acoustics rely on the hardness, shape, and size of the material. In which case, a gourd is a hard and often thin material (after gutting it). Typical 3D printing materials will have a minimum thickness which may get in the way of achieving the same shape of the gourd resonator and plastics are typically going to be softer in hardness than your gourd.
So, in short, I think if your try to replicate the resonator with 3D printing it will not sound the same. That may not be a bad thing, depending on what you're looking for.
Also, who's to say the resonator has to be shaped like that? 3D printers allow us to manufacture parts that have historically been impossible to make and many instruments that we use today were designed hundreds of years ago with far less advanced tools available. I say its worth trying a replica of the gourd and then exploring other shapes to print that may affect the tonality of your instrument.