I would grade the coin VF-30. Price guides will have it worth slightly more, but the price you got on eBay is pretty much exactly what I'd expect. I was appropriate.
29-D, although it had some issues, is not noted as being one of the worst struck in the series like say, 25-S. Furthermore, this is actually not really a great strike if you ask me. It is probably just slightly above average. The horn looks to never have had a pointed tip, just a dull one and the buffalo's head and upper back are just decent. The coin is really nothing special as far as strike goes. With the mintage somewhat accessible and it being later in the series, enough surviving 29-D examples survived with full detail for it to have never been a problem.