hi mate there are lots of options of different turbo manifolds for zetecs and lots of prices as well , lets start with the cheapest first
first is cvh erst but you will have to drill and tap the head as they have different bolt patterns £40 for manifold and £50 for drilling and tapping
focus rs manifold but you would need to use a gt28 turbo , £100
then its the obx pretty cheap but have heard that they crack and on more than one
i think they are about £250 on ebay
then theres the hansen turbo manifold that jamsport uses , very well made and built
again i think about £650
then theres area six manifolds which place the turbo over the gearbox , there are 3 stages of build .
cone design good for 500+bhp £550
the new merge collector will out flow the cone design (600+bhp) £650
with merge collector fitted with 2 v band clamps , 1 at the end of the merge collector and 1 at the turbo flange allowing the turbo to be fine adjusted to every cars engine bay (600+bhp) £850
all area six style manifolds can come with external wastegate options
then theres primary designs manifold , very similar to the obx manifold but alot more costly at £1000
or you may be able to get a wrc manifold which cost anything between £700 to £1500 if you can find one and would most probably need cutting and fabricating to fit your engine bay
hope this helps
cheers paul