With virtually no information to go on your search will probably be about like trying to find a needle in a haystack the size of Alaska, unless some family member has photos. Probably the best possibility otherwise is to contact NARA or the NPRC to attempt to locate their records, which may (but usually doesn't for pre-Korea vets)contain an ID photo.

You'll need the vet's full name, date/place of birth, and as much other info as possible if you have no branch of service or unit data. The snag is that they only release complete records to next of kin (parent, spouse, child ONLY - they don't consider neices/nephews and grandchildren "next of kin"), therefore someone who fits that profile will have to fill out and sign the request form.