Yes, either of those target stocks would fit. However, the speed loader cut stocks would be quite a bit later than your Highway Patrolman. For the N frame, those showed up in the early 1980s. The footballs would be correct.
Having said that, there are a couple other considerations, with respect to the original configuration.
1. Depending on how high that S prefix number is, diamonds might not be correct. The N prefix started in 1969. The diamond on N frame target stocks was dropped by virtue of a management order dated December 28, 1967. On the Magna style, it happened earlier - the management order was issued on January 11, 1966. Using up the old diamond target stocks took until sometime in 1968. Perhaps a few showed up later, but those would be scarce at best. Diamond Magna stocks probably disappeared sooner.
2. Standard stocks on the Model 28 Highway Patrolman were Magna, not target. True, some did ship with target stocks, but those were an extra cost option, which, from time to time, were ordered by dealers (so not necessarily a customer special order).
...Ben
