Console mounted fishfinder

[cswashburn]

I have a 96 Stratos boat that has a factory installed lowrance fish finder in the console and in the front plate by the bow. I would like to replace both these fish finders with a simple fish finder around $150 a piece, but cant find any that will fit. The old fish finders measured 5 inches by 5 inches i can modify the hole slightly, but there is not a whole lot of extra room. Any help would be greatly appreciated.
Thanks