Pellets are very simple to use, and usually 100 gr. in a 50 cal. behind a bullet in the 250 gr. weight range works fine. Downside to pellets ... I have found pellets less consistent than loose powder, but it might be worth a try. And pellets that I have found come in 50 gr. increments. Not a simple way to custom a load other than try different bullets. I use loose powder.

As for a scope? I am guessing you may be hunting both woods and ag fields???? I suspect that some of the ag fields might be expansive enough to test or exceed the reasonable far distance that your ML is capable of. Something like a 1.5-6x40mm or 2-7x40mm would be a good choice.