So I'm thinking of putting something like a Garmin striker 4 on my bow, but obviously it's small and low.  Does anyone use, or has anyone heard of raising the bow finder up on some kind of pedestal?

I saw a guy with one that must have been over 3 feet long.  I don’t know what he did when motoring. I only saw him fishing.

What you are looking for is a RAM mount. I think they make different heights. This is the one on my boat.

Ram mounts are good and they make a wide verity including longer units like the one posted above.

I always take my sonar units off the boat when trailering and Ram mounts are easy to mount or remove the sonar unit quickly. My bow mount raising the sonar unit about 12" higher then the standard deck mount. This allows me to see it better and make any adjustments easily. My consol mount keeps the sonar unit to the outside of the windshield, easy to view and still see what is in front of me.

Tom

PS, Ram makes a 18" extension pedistal. My front long arm mount is 9" plus the base mount and adapter plate is about 12" overall.

I use a Ram mount as well at the bow.