So you're going to replace inert and harmless silver amalgam fillings with resin fillings? Which break down and need to to be replaced about every 5 years and are a constant source of bisphenol A? (Funny how composite resin fillings never get the rap that mercury alloy amalgam fillings do)
You could try getting porcelain, alloy, or high noble (i.e. gold) milled restorations in the form of an inlay or onlay. But, oh wait, they use RESIN CEMENTS, so you're still getting poisoned.
What about gold foil restorations? Sure, they can be used in very small and specific situations. Better hope your tooth doesn't fracture from the repeated hammering required, and that the pulp doesn't overheat from the friction.
If tl;dr, don't worry about the mercury in the fillings. It becomes inert once it sets up, and you consume far more mercury from seafood, vegetables and plants, and other trace environmental sources. Getting them removed and replaced with resin fillings will be an uncomfortable, long, and expensive process that is unnecessary.