In my opinion this is a very interesting, good, but possibly misworded, question. I would like it if you rephrased the headline alone and asked it again because I am interested in the answer. If you phrased it as "What are some options to maintain a bug bounty program for a small company on a budget?" or something along those lines and include all of the introduction and explanation that you provided earlier, then I would be surprised to see it closed, because it is an interesting question. 

The problem, as mentioned in the comments is that you will never get a definitive answer for this question, and rephrasing it so as not to encourage a definitive answer prevents answerers from having to begin with "*Well I know that this is perhaps not the best possible answer but one solution might be..."* 

Perhaps you're original question could have been easily edited to fit Security SE's guidelines, but that's not a big deal. I hope you re-ask the question in a way that encourages suggestions rather than definitive answers because it is a tangible, real-world question worth asking.