Will compression stockings help with low blood pressure?

Those mostly help with lymphedema.

Doesn’t it seem counter intuitive to compress/restrict blood flow when it’s already low?

Yes, this is a recommended treatment option.
http://www.nhs.uk/Conditions/Blood-pressure-(low)/Pages/Treatment.aspx
(it won’t link because of the brackets)

I don’t know the answer to the OP, but to address @Blueroses question, compression stockings compress the superficial venous system (surface veins) which are responsible for a very small percentage of the blood returning to the heart from the legs (around 10% I believe), since most travels through the deep system. Narrowing the vessels increases the velocity of the blood flowing through them (e.g. think of putting a nozzle on the end of a hose).