Your additional info on how you plan to use that good looking RR does change how aggressive the cam should be.
To answer your question on milling the heads : yes. I used the calculator in this post with your bore and stroke and added a 77 cc combustion chamber with the other provided numbers and came up with 11.3 SCR. I have a set of Eddy's that were milled to 77cc's. Considering that the intake face needs to be milled as well, that may be as much as you can go with a street application. The valve cover rail get a little small for sealing. So, even with the zero deck and the head milling, you still are well below that 12 to 1 number your concerned about. Just to let you know you may not be able the get the compression high enough and be safe in a street app.
You may be spot on with your cam choice even tho it does seem to be a little small. Bear in mind that a stroker motor (this may not be one) does like or eat up cam duration. So this is a consideration for you.......like you need another question..............right?