The cost of buying the voucher from sun site is $300 or Rs 7500.
I believe you are from India. If so you can always contact a NIIT office in your city. They are one of the centers where you can take your exam (i took mine at one ). As of 31st March 2009 they were selling the voucher for a sum of Rs 5000/-.
The validity of the voucher is one year from date of purchase. (However it is better you enquire about this from NIIT when you contact them).
The topics of SCJP are follows:
Section 1: Declarations, Initialization and Scoping
Section 2: Flow Control
Section 3: API Contents
Section 4: Concurrency
Section 5: OO Concepts
Section 6: Collections / Generics
Section 7: Fundamentals
No. It does not cover AWT, Applet or Swing.
I hope i have been of some help. ALL THE BEST WITH SCJP!!