Here is the solution that I came up with.
I bought two matching cutting boards from Meijer, I believe Walmart sells very similar ones.
For the sink, I use just the cutting board, it is large enough that it will not fall
into the sink, and sliding it right up against the faucets and the upper cabinet support, it remains quite stable while stationary. Have to move it during transport.
For the stove I added spindled Galley Rail that I got at Lowe's in the molding area. The employee couldn't tell me where to find it, but I just kept looking and found it. One package was enough to support three sides of the cutting board. I left the fourth side open so that it is easy to slide into position. When travelling, I turn the stove cover around, so that what is the front side goes to the back. This hooks the cover onto the stove, so it stays in position while traveling. At least so far.
The Galley Rail falls apart when you remove it from the package, so you need to have wood glue handy when you want to re-assemble after cutting the rails to length. I screwed the one rail to the cutting board, then added glue and re-assembled the spindles and the second rail on each side. A short length of 2x6 as a persuader made seating all the spindles easy once they were lined up properly. Sounds more complicated than it was. All together took about a half hour. I then just placed some weight
on it to hold it all together until it was cured.
Full disclosure, I got the idea from a Youtube video, but it had no directions.
Here are a couple of pics: