Anyone wanting to create volume needs to understand the speaker sensitivity rating. Currently your recommendations here range from a low of 87db to a high of 99db. This rating and the amount of power used determines the maximum volume of the system.
Every 3db lower in speaker sensitivity will require double amplifier power for the same volume capability. So if you have 50w on the 99db speaker, then the following would be the required power for lower sensitivity speakers to have that same volume capability,
96db -- 100w
93db -- 200w
90db -- 400w
87db -- 800w
IMHO, I doubt any speaker with a sensitivity below ~93db will be suitable for your situation.
