You might be able to do something fairly accurate on the cheap. I came at this as a photographer, and already had pieces/parts. I'll circle back around to parts as the last bit.
I had a triangular piece of tempered glass, each side measured about 12". So not terribly large by any measure.
I took one of my tripods, consisting of legs (the parts that telescope and hit the ground), head (the part to which the camera, etc attaches), and a quick release system. The quick release system connects to the tripod head, and has a lever to operate. Normally, you attach a camera or whatever to a tripod via a screw. With a QR, you attach the QR via the screw one time, and then flip a lever to attach your camera - your camera gets an inexpensive plate screwed into it. I apologize if you know all this, I am trying to tell you exactly what I did - no more, no less.
I glued, with cyanoacrylate, a QR plate to the triangular glass. I can now take the tripod, set the leg height, clip the piece of glass onto the head, and I have a small table. I then place the Sharpmaker base on the table, and using a small woodworker's clamp, the SM gets clamped in place so it doesn't move.
The tripod head, of course, is fully adjustable in any direction for any angle. If you have a good head (mine is only 1/2 baked) you could read the angle you're setting directly. I just place an angle finder on the glass; I use that to set the angle of my work surface. It takes under a minute to make this setting. The angle of this setting is combined with the (say) 15 degree angle of the SM rods. You're ready to go. Of course, the first couple times you'll probably incorporate the sharpie trick (not the Sharpie trick the girl on Tumblr does) to check your settings.
This angle is easily repeatable. I keep a spreadsheet with the angles I've used for each knife.
I can raise or lower the SM, so I can use it lowered and remain seated, and still have good perspective of what is taking place.
I don't need safety guides any longer. The SM is clamped in place, and I end up sitting around with my thumb up my butt which keeps track of one hand while I sharpen with the other hand.
The tripod: I would post a WTB here. You can also start shopping, there are plenty of used tripods available via the web these days. The legs and head I have are rated for a 40lb load. You do, in this case, want to buy something that is overrated specwise; if the head or a leg breaks while you're sharpening, that might just be messy. If you need some specific recs for where to buy, I'll happily give you some ideas.
Good luck!
