so $10 is 8.32d (medieval pence), and that pdf says 0.5d/lb of charcoal and 12d/lb of incense, making the ratio 1:24. So (1*8.32)/25 spend on charcoal, and (24*8.32)/25 spent on incense. 0.3328d gets you 0.332*2 lbs of charcoal or about ~300g ~10oz of charcoal.
~8d spent on incense gets you the same weight of incense...