Looking for a Tool for Manual Stim

Enjoying all my Aneros models (Helix Syn, Maximus, Progasm, and Peridise) since I began early in 2013.

Sometimes, usually with the Syn, if not much is happening in a session, I'll get bored and using a hand, grasp the Syn by the handle and kind of twist side to side or front to back. This usually produces a very pleasurable direct response to the prostate, albeit different from the typical mini-o's that I am now used to. I would like to explore this type of stim further, possibly in a more aggressive manner, but due to the awkward angle and flexibility of the handle, it is difficult to maintain this movement for very long. For a while, I was also in a habit of "cheating" by inserting the Helix Syn and mounting a soft upholstered chair arm, grinding away to explosive HFWO's. Because of this, I am sure I could also use a manually controlled device to get great o's.

I also use a Lelo Billy vibrating massager occasionally, but due to its wider width, I can't achieve the same mobility when working my ass with it. And most of the dildos I have looked at seem to be also too wide for this.

So the reason for my post: Is anyone aware of a narrow necked device intended specifically for manual stimulation of the prostate? I am picturing something like the Helix Syn, but with a long handle parallel to the shaft. Something such as that would allow good hand control and I am certain it would produce excellent prostate orgasms with a focused effort.