u can get it from either of three places:
1. Your local DOL office, where ur LC was initially filed
2. Your regional DOL office, where ur LC was finally approved
3. BCIS
You would need to file an FOIA (freedom of information act) request. BCIS has a form for it, whereas DOL only requires u to fax/mail a letter.
In my opinion, it is easiest to get it from regional DOL office as the local office does not has all the info, whereas anything to do with BCIS can be painstaking. Call 1-877-US-2JOBS and ask for the FOIA officer/regional DOL numbers.
goodluck!
-ab