Now is the time to buy some M-L supplies, where any are left. I swung through a Dick's Sporting goods store yesterday & bought some 250 grn 'Shockwave' bullets for $6.97. I also got a pack of 300 grn to try. Check a Wal-Mart if they sell any type of gun stuff. I'd go right to the new Blackhorn 209 powder, mail order if you have to. You will need a bullet starter, powder measure for loose powder, a few speedloaders, & maybe a powder flask. I would read up some & buy the stuff individually, no great hurry at the moment. After that make sure you have some cleaning supplies & keep the gun clean after shooting. I also like the regular SST/Shockwaves over the 'easy-glide' ones, your bore/techniques may differ.
I don't like a really busy reticle. I have a Burris 2-7 with the BP reticle on my Knight. I still mostly just use the center X-hair though. Shotgun primers are easy to find, I use CCI mag. You may have to do some testing but I'll bet 100-120 grains of B209 under a 250 Shockwave/SST will get the job done nicely.