This is the set collector's dream set to finish. A difficult if not nearly impossible one to complete, there are high numbers that are short-printed, popular stars, and of course it is the first "set" put out by Topps.
Speaking strictly about the Phillies team set, the 300 and above cards will run you easily into the $100 range for VG condition. Maybe more depending on the seller, venue (Ebay, store, card show), and economy. I personally have only one of them, #352 Drews, and it ran me 80.00 for a G conditioned card. Ugh. These cards are out there though and if money is available- go for it. The set is worth it.