ok, for anything 2.5" or less, the coils are 138 plus shipping per pair. but, for anything more than that, you also need a new upper strut mount to allow more down travel on the street so that you don't pick a tire up while turning or something and hitting a bump/dip at the same time. the mounts are about $75 for a set. they don't come with the bolts either, but they should be cheap.

as far as changing the coil seats? well, you can make them smaller if that'll help, but you can't go more than about a 1/4" wider because they have to fit inside the strut tower at certain points during strut travel. the coils measure about 4.5" outer diameter, about 3.5" inner diameter and are about a 1/2" thick, maybe slightly thicker, but they are measured in mm, not inches, so don't take these measurements to heart.

it's almost as cheap to go with these custom coils as it would be to go with junkyard or new stock coils for anything else.

one thing with those TJ coils Dennis mentioned: he also said they were very stiff, which can be a good thing or a bad thing, depending on your preferences, driving habits, load carrying habits and condition of your shocks and people who ride with you as well as what you expect out of your vehicle as far as ride quality goes. not recommending against them, just recommending some research on your part into spring rates and such.