Everyone should have paper charts. Even a large chartplotter can't match the size and detail of a paper chart. Going with a handheld GPS and paper chart is great inexpensive solution. Did it for years. The most useful feature is waypoints. No need to plot positions on the chart from a string of numbers. You know direction and distance to your next mark in realtime. Look for a unit with a builtin database of the USCG marks. No need to enter the data (and possibly make a mistake). With an inexpensive graphing unit, its just a matter of finding the mark on the screen map, selecting it, and your done.
Suggest you reconsider a speed instrument. The log feature in particular is very helpful in DR navigation.