They sell Dark DME
, which I'd use instead. Just take the amount of LME your recipe calls for, multiply it by 0.85 and that's how much DME to use for about the same gravity points.
So if your recipe called exclusively for, say, 4 Lbs Dark LME @ an OG of 1.030, 4 Lbs LME*0.85= 3.4 Lbs Dark DME
@ OG 1.030.