Engine getting sluggish

There has been no work (except a new water pump) done to my NA engine.  I seem to be getting left behind in traffic by just about every other thing on the road.  So, I'm wondering about an engine recondition.  Does anyone do changeovers for the MR2 these days, if it ever was an option.  Or do you just have to take it to the local engine rebuild shop and say fix everything (rebore, new pistons, bearings etc).  Has anyone done this recently and how much did it cost you?