47K ohms is actually 47,000 ohms. The 103R should sound quite good into the 100 ohm load; the other setting that you should try out is the 30 ohm load. It is quite possible that it will sound even better to you there. Don't worry about it if it doesn't as this is a subjective hobby and there are many things to take into account such as system synergy, related pieces of equipment etc.
My advice would be to get 15-20 hours on the cartridge tracking it around 2.6 or 2.7 grams using that 100 ohm load and then try the 30 ohm load. I'm not familiar with the Dyna phono stage, but it sounds like the "resistance" setting is actually a gain setting, with "high" giving the higher gain. With the lower output of the 103R vs. the straight 103, it would make sense that the R would prefer that "high" setting.
Good luck and enjoy your 103R. It is a great cartridge (especially for the money!!!).