186093 Events Calendar PHP script

I would like a simple php script which I can integrate into my gaming website. The script is a simple, text based events calendar that shows day,date,time of the next scheduled game and who will be able to play. Members must have their own individual log ins to allow them to create a new entry, amend their availability and add comments. Full details can be seen on the attachment. This is only a small site and I have a limited budget, so cost will be a major consideration. Thanks