Excellent. Bigger would be better in this case but 30 people is enough for a little fluidity.
How many people are above you? Like, how many levels between you and the top? Because the first move is to tell your immediate supervisor that you want something with more growth than your current position, and you're willing and eager to take on the additional education necessary to get that.
This puts you in a position of being ambitious and it opens the door for you to interact outside of work. Small businesses get a tax break if they pay for some or all of your tuition so they have an incentive to help you with your retraining. It also likely increases your loyalty and improves their retention.
Which is not to say you're going to work there forever but if you show that you want to stretch your wings, the impetus is suddenly on them to make YOU happy (assuming you do the work).
Not having an idea of what else you want to do actually works to your advantage. That means that they can fit you in just about any position. Not only that, but many land grant schools have night masters programs; around me I can get an MBA, a JD, a masters in computer science and who knows what else all in 3-year programs that happen only on evenings and weekends.
A headhunter is not going to help you. Your salary is not of the calibre that rewards a hiring professional to help you out because there are many candidates who can do your job. The trick is to become a better candidate and increase your value while also increasing your exposure.
You've been there nearly four years, and they have promoted you. There's no reason not to work within the system first.
Ask upstream and see what they say. I'm optimistic and curious.