Is it? I know my polks are going to cost to about 150$ for my front Polk pair, x2= 300$ + 1 pair for the seat speakers 100$ = 400$ plus tx im guessing a good 450 $. That is just a Polk set up... There are much more expensive speakers out there.... I just love how crisp Polk sounds for the $...
And for the original poster, I am sorry to add on something you should have known from the beggining... (I 4got to mention oops lol...) Since you are using component/good speakers you might want to power those up with an amp... I think you can shop around for some pods here and ebay might do it too. For speakers try ebay also... Just make sure you are buying New speakers not used one... After that you might have enough left for a nice little amp to power your speakers up.... Here is a set up I would use...
http://cgi.ebay.com/POLK-AUDIO-DB52...39:1|66:2|65:12|240:1318&_trksid=p3286.c0.m14
http://cgi.ebay.com/POLK-AUDIO-db40...39:1|66:2|65:12|240:1318&_trksid=p3286.c0.m14
http://www.edesignaudio.com/product_info.php?cPath=1_22&products_id=46
And this set up is without the 6 1/2 speakers pods.... Just a little quick set up I would do (note) shop around more, go to circuit city even and hear the polks out and the kicker ones... Infinity speakers are gr8 2... You can find those at car toys and hear them there... Dont buy emm there because they will be more expensive.. The link to the amp dont even mess with... I highly recommend that amp, it can make a pair of fing Sony's Xplods sound incredible...
and you should sit up around 500$ at the end of the day... And if I am correct you dont have the 2 extra speakers on the shoulders area backseat... I have a friend with a 87 supra and his does not... Just trying to clear that up...