You are low but maybe not considering what you said. However, once you get up into a reasonable range the big guns pay more attention to uniformity of the readings between cylinders than the actual value. Actual value can have variables including operator expertise, gauge errors, engine temp, stuck rings and such where the differential pressure eliminates a lot of the guess work. 10-15 psig max on my 90 and 120 or above is ok so said my maint manual. Sea Foam is available at WM and most auto stores for about $7 a pint can. Go to the archives and read up on the "decarb" process which not only decarbons a carboned up engine, it also loosens up stuck rings which can improve your compression bottom line.
Mark