Perhaps for the Arulin'Holm or just general blood-letting knife. To represent the Eluvian/the shard Merrill kept? Subeta apparently doesn't have a ball of string or twine, but this for the ball of string Varric gives her to help find her way around? Couldn't find any deer items at a quick glance that look like a halla, but maybe this for the wooden halla carving you can give her? It's not wooden, but it's white like a halla. >_> For Merrill's 'furry friends' she shares her house with. Demony/Blood Magic. For the Dalish tattoos?
Hope that helps! :D