Easy way to tell if the house is "too tight", does the stove have good draft ? If it has good draft all the way to max output, then the house is not too tight, ....... but if you see the sliding glass door bowing in, . .
If it's marginal, then you will need to do something - especially when you move the Clarion into the house too.
Being the devil's advocate, . . you then have to determine if installing an outside air source will at anytime over compensate and bring in more cold air because of the house's stack affect ? I had that happen using the ash pit of my fire place as an outside air feed. To control it, I had to make a linkage and control rod that allowed me to set the right amount of ash pit door opening so it wouldn't be too much opening. And, I had to make sure to close it when the fireplace was not in use, or the living room floor got cold as the house's stack affect pulled in cold air.
Very often, when this is done, the outside air source is attached directly to the air inlet of the heating appliance, so that it doesn't leak cold air into the living space, or the heating appliance is in a sealed area. Not sure how you would do that in your situation.
I had to do this when I built the oil-fired radiant floor heat system in my shop. I didn't want shop dust/fumes getting to the oil burner so I built a closet around it and put an air inlet duct under and up against the stove pipe that then extended down near floor level of the cabinet so it would not bleed off warm cabinet air when the burner was off. The exhaust going up the pipe helped heat the incoming air and reduced the chance of oil burner condensation.
I wonder if there is some way to jacket the stove pipe and use that as the incoming air ?