Sounds like a location issue to me.
I've been in markets where the taxes are higher on model matches and are worth more than in a neighboring town with the same model where taxes are less because the higher taxed town is preferred due to school districts (paid for by the property tax).
The federal registry for historic districts is, to what I remember, more of an honory acknowledgement. The federal government doesn't have much say in areas unless they are national parks. I suppose there are some there or here that receive federal funds but, to the best of my knowledge, it is the local historic district's bylaws, zoning, etc., that is typically run and set by the local municipality, that determines the extent of preservation, etc. So even going from one town's historic district to another is a bit iffy.
But in my opinion, as long as you have a couple of sales from the subject's historic area and can firm up a good location adjustment, then in that situation where you have no other choice, you can just look to extract that location adjustment and comment on why it is necessary. The higher taxes can be part of the comment.
