Need Advice/Help on Hopper Vibrators

I have just recently rented a nice Wilson PaceSetter hopper that has slip in brackets installed for a vibrator on each tub.
I am looking for the brand of vibrator that slips into these brackets but cannot seem to come up with anything on a Google Image search. Timpte has a very similiar bracket type arrangement but even so, I cannot seem to pinpoint the exact brand. A removable/portable vibrator to work with these brackets are not anything that Wilson seems to offer and the prior owner is unavailable for questions.
Because this trailer belongs to another party, I do not want to attempt my old method of removing the meal product I normally haul by beating on the hopper with a mallet. I realize that this can be an efficient way (at times) in helping to remove material but in the past, this has resulted in dings and dents to the junk hopper I used to pull.

I am also toying with the idea of the suction mount type of vibrator but have no experience with these.

Any help or advice would be appreciated.