another directions to go is
purchase a new/used bookshelf speaker and build weatherproof encloser. Not sure exactly where you want the speaker placed, but if you are close to your house, mount them under your roof eve (overhang).
You can get great sound from a bookshelf, save money and get superior bass verses a dedicated 'outdoor' speaker.
example:
I use a pair of Infinity Primus 150 mounted above my deck under my roof overhang. Two plus years (remove during winter) and they look/sound great. They sound great and will bet they outproform most/all outdoor speakers.