Your boss has the job of keeping things in balance. That simply means that his/her job is to maintain or control the costs of doing business. You, as an employee, are one of the costs of doing business. If you want a raise and the response is "that is not in the budget now," you should assume that is normal. How can you change that reaction?
If your boss asks you to speak somewhere as a representative of the business you should do it. Prepare, accept the confidence placed in you, provide a "leave behind" for your audience and provide your audience with something they need and that they can use. When you are finished, allow them to pick up your "leave behind," which should include copies of the slides you used and a cover sheet that contains your contact information.
When the audience returns to their work place they may provide to human resources or their boss the name, or names of folk that might make good additions to the business. If you in turn are asked to consider a position in another business, they may offer you more in total value than you are currently getting. If they do, because of the cover sheet (networking) you have an option that you can use to "allow" your boss to counter and therefore provide you with the raise that otherwise you would never have been offered. That's what we mean when we say, "Work at the pay of your choice."