I agree with Ken that you may not see challenges from other companies doing exactly what you're doing, but there are still challenges for you ahead. You may simply not have uncovered them yet. It's good that they're not plentiful, and nothing says you won't be able to overcome those challenges when you do face them. But the first question I always as an advisor when someone says they don't have competition, is "Why?" Is there something about what you're doing that didn't generate enough demand for someone else to solve the problem? Were there competitors and then they went out of business because people didn't care about solving the problem enough to pay money for the service?
This is part of market research, finding out if there is a pre-existing demand, instead of producing a solution and hoping to build an interested audience. I refer back to the invention of the car. There was no need for cars. People weren't crying, "Oh, I wish I had a faster vehicle because my horse is too slow." They just weren't. So, the first car manufacturers had to revolutionize the culture of transportation, a MASSIVE effort, as people didn't even want cars when they were first available, no matter that they solved problems the manufacturers perceived the public had.
I'm not sure whether you phrased it imprecisely to say that you want advisors while you fund the business, or if you were actually looking for both advisors AND funding. Ideas tend to be cheap. Business plans not so much. So while you can always benefit from solid advice, turning that into a plan that will demonstrate to investors that their money is safe with you is a different issue.
The exhibition world is fairly confined. You have some very large and very small individual show producers, and you have a very calculable number of exhibition companies that manage shows for other people. Not knowing your service I can't guess which is a better audience for you.
Are you currently subscribed to any of the three magazines in that industry? Do you attend the convention for convention/event planners? Are you a member of the trade show producers association or meeting planners association? All of these places are sources for potentially useful advice and maybe even advisors. Until you're engaged in active conversations in that community, it would be hard to stir up interest for most to give you specific advice on your idea.
At this stage, I'm only guessing, but you might benefit most from the kind of advisor who helps you translate your idea into a plan. This does not need to be industry specific, because it's pretty much the same mechanism for any business. You can later refine the plan with someone's assistance who is in the industry, but you don't need to necessarily start there. I recommend, especially for a first business venture, starting with the people at SCORE. It's free coaching for whatever stage of your business you're in, and they will continue to work with you (mostly retired executives) to move you along a smart path, wherever it is you need help.
Of course there are advisors here on FD, that's part of why FD exists, and you can search for them here specific to your industry.