Here is an idea. Do you have any major universities or colleges nearby? Google search for them and "technology transfer" to see if they have a technology transfer office. You can then call them and ask them who they use in your local area that has expertise in the subject matter of your invention. They might even be able to tell you how much different attorneys charge.
As a last resort you can search the patent office website for approved agents and attorneys by zip code:
https://oedci.uspto.gov/OEDCI/