There are a few questions - what have you done with the other chapters? My feeling is, they should be together. But even if you publish in the same publication, they'll be split up by all the other stories. I'd be tempted to create a publication for the purpose of keeping the chapters together, but that obviously doesn't help the problem of a limited readership.

There is a pub called Illumination Book Chapters - they invite first chapters of novels, so people can then go on to buy the book if they want to read the rest. At least, I think that's how it works. You could look it up, as a possible home for the lot, but I think it's for first chapters.

I hope you find a suitable solution.