I take the normal pattern to Office Depot and have them enlarge them. I have had to have them do some on the plotter because they were too big for a printer.
I have never used Baltic Birtch. I buy 1/4" plywood from Lowes. My Lowe's has Maple, Oak and the underlayment for flooring has one side that looks great.
The model number is B04510. It is an older sander. I have had it 30 to 35 years. I sand all of my fretwork and any other wood project and have never had a problem.
Yes I know what you are going through. I have had three neck surgeries. I have C4, C5, C6 and C7 fused together and two metal plates with eight screws. If I can sit at the saw for 1.5 hours I am doing good.
I bought a Cutech jointer with the spiral cutting head. If I was going to buy a planer I think I would get the Cutech with the spiral cutting head. Check them out along with reviews.