I tend to have low blood pressure as well, possible a family thing as my nan and grandfather (from different sides) did as well.
I do get dizziness (though have menieres as well) when it goes really low (it often bobs about between low and normal), mine was lower than yours when I had it tested the other week.
I had upping my salt intake suggested to me once but not for me as it makes the menieres worse and is generally unhealthy unless medically condoned.
I am monitored quite often due to immune suppressants I'm on and they note it and don't really get concerned unless it's affecting me eg fainting and dizziness.
You're not in the danger level (90/60 or below) as such but if you have other symptoms or problematic ones or are worried have a chat to your GP.
Some more info here...
http://www.nhsdirect.nhs.uk/articles/article.a spx?articleId=490