Some ? about my 8 3/4

The reason I ask is a guy had a rear out of a dart sport but he does not know what its out off think its a 8 1/4 sbp but will bolt right up and will hold up to my 360 fine but I did not know were you could get 8 1/4 drum brake parts.I was going to see which would be a better option.looking like the 8 1/4 is best.