I would call Airmar. Im sure you are familiar with them but if not they supply all of my transducers for my boats. Im sure they can come up with a cost conscious solution for you. airmartechnology Dot Com
Also check out this blog about marine electronics. this guy has definitely done what you are talking about and im sure he can walk you through it. panbo Dot Com
For some reason i cant post links so you will have to retype them.
Good Luck
Panga Man
From there contact page:
Airmar does not sell transducers and spare parts to electronics dealers, installers, and end users. You must either contact our two subsidiaries, your electronics manufacturer, or local installing dealer:
Gemeco Marine Accessories is Airmar’s distributor that services all marine electronics dealers in the USA and Canada.
Their contact information is phone: 843 210 7000.
Airmar EMEA services all marine electronics dealers and distributors in Europe and the rest of the world.
Their contact information is phone: 33 (0)2 23 52 06 48
If you have questions regarding your fish finder or instruments, please contact the manufacturer of your electronics.
Please check our Frequently Asked Questions page before calling or emailing airmar. There are hundreds of questions and answers that are updated weekly regarding transducers.
If you are looking for information regarding compatible transducers with your electronics, a complete list is available in our cross reference guide
Airmar can only answer technical and sales questions about transducers. If you have specific questions regarding your transducer, please provide the part number that is noted on the white cable label tag located near the connector. Please advise the manufacturer and model of your fish finder/instrument also. For example, all of our part numbers are eight digits (example31-256-1-01). This will help expedite the reply.
Airmar's contact information is phone: 603 673 9570
AIRMAR Technology Corporation is located at 35 MEADOWBROOK DRIVE, M
