It used to be $6, then it went down to $1. I am not sure exactly when, but it appears to have changed and is now $5.
Receive Sweepstakes/Prize Promotion Cash for Global Poker website sending a mailed request. US and Canadian (excluding Quebec) Participants can receive Sweepstakes/Prize Promotion Cash by sending a stamped #10 envelope, hand written, to the following:
for US residents: VGW RMG LIMITED, GLOBAL POKER SWEEPSTAKES DEPARTMENT, PO BOX #8486, PORTSMOUTH, NH 03801;
for Canadian residents: VGW RMG LIMITED, GLOBAL POKER SWEEPSTAKES DEPARTMENT, PO BOX #990, 135 WEST BEAVER CREEK ROAD, RICHMOND HILL, ONTARIO L3T 2C0.
Participants must include their full name and return address to the front of the envelope and words: "Sweepstakes Credits:" followed by the current month and year (example: Sweepstakes Credits: January 2017). Limit one request per outer envelope.
For each request a Participant submits the Participant will receive 5 Sweepstakes/Prize Promotion Cash.
The Sweepstakes/Prize Promotion Cash will be added to the Participant's account. NOTE: Participants must ensure that their hand writing is legible. If the Participant’s hand writing is not legible, the entry will be void and the $weeps Cash will not be credited to the Participant’s account.
https://globalpoker.com/page/sweeps-rules