I agree that the RST shells will get the job done. At the close range on the skeet field the slightly lower speed won't make any difference and you will definitely notice the difference in recoil shooting a light double gun. I agree that you should get set up to load your own so you can have what you need.
Is your gun chambered for 2 1/2" or just shorter than 23/4"? There are a few shells sold as 2 3/4 when they are actually 2 5?8 when empty hulls are measured.

Byron