That's a 175A Skylark. A geared Continental 0-300 which was seriously underestimated by a lot of people in the 60's. Much in demand these days for a 180 Lycoming conversion, but still a collectors piece by any standard. Unsure if these have SIDS considerations. (Also a "Mouse for $23K and a PA-28 140 for $26,500). Fuel now becomes a consideration. Probably best stick with plan A for the exercise. Remember the best aeroplane in the world is the one a bit bigger and a bit faster than the one you have. The block time quote idea has merit for comparison.