if search around on google you can get them for about 10bucks, interface card with the 8515 chip, 25bucks at this site
this site has the serial port already on the card so no soldering needed, in the past we always had to solder on a serial port ourselves (like 4 wires, not a big deal)
all the 8515 card is used for now is to receive the CW's (control words)
the 8515 card needs to be married to the provider's receiver or whatever receiver you plan on using it in
same as the captiveworks setup meda, cept your using provider's receiver and the 8515 interface card instead of the captiveworks receiver
still need an iso reader/programmer, a 24x subbed card, a pc constantly running and setup as a server, so in actuality the captiveworks is easier to card-share with