Pam,
HUD says flat out that if the labels are missing, the house is not eligible for FHA financing. Stop work! Report the problem to the lender and let them resolve the issue. This is now a problem for the homeowner and the lender to work out. Not you. They may be able to go back to the manufacturer and get the necessary certification but finding all of this out is certainly not part of the appraisal process (unless you are getting paid by the hour).
5/10/2003
Interestingly, we just had an FHA sales Thursday that had a couple of those old testing labs seals on the two halves and everyone thought it was a HUD house. Owner thinks it was built in 1979. Richard, the Appraiser, does not think so. Everything tells me it is pre-1976 and pre-HUD Code. I'm giving them, the owners & brokers, about 5 days to see if they can prove me wrong before I report to my client. Time will tell but I will not put any more work into this report until I have something substantial to proceed on.