8051 based project,need help,BARCODE????

hi there
iam working ona proj which is based on 8051 microconlr,the proj is all bout "CARD SWAPPING".
its basically a security system which works on usin a specific device when a specific card is swapped with a distinct code on it.
sicnce "CODE" is to be used i want to know whether a "BARCODE" wud b viable for the application,
1)foolproof wise
2)complexity wise
3)price wise
what wud be barcode readers all bout.do they have specific ics available for it,if yes what cud be price rane for them.
can any one help me with the interfacing of the 8051 with rest of the stuff,who is extremely comfy the controller.pls let me know

No problem with the controller, but hard to find the optical components and sensor IC. ( maybe You can canibalize it from old FAX-machine)
I mean: buy one, it's cheaper...