If you'd said that you'd be away for a week or two, I'd have strongly advised you to poll your immediate neighbors, as I'm 99.9% sure that you'd find a cat lover who'd be willing to care for your kittes.
But, you've added a time element that changes all that.
If you're thinking of being Down Under during our Winter here, you might very well find some long-term "renters" interested in a deal! But, if you're heading out during Central Florida's Summer season, you'll have more difficulties!
There are a number of rental agencies in the tri-county area who can undoubtedly help you find a long-term tenant willing to care for the cats!
As a cat lover and a subject of The Cat's domination, I strongly hope that you will interview your potential clients thoroughly to assess their feline-friendliness. In my view, that'll be more important than their being capable of carig for your residence!
SWR