Primarily Petroliana Shop Talk Forums Shop Talk Petroliana Forums Known & Suspected Unmarked Petro Reproductions Finding an Authentic Standard White/Red Crown

I looked for this answer but didn't find anything. Can anyone please help with identifying an authentic vintage Standard White or Red Crown porcelain sign? The markings are so inconsistent. What are they supposed have? A few examples from Ebay. Which are real and which are fakes? Thank you

300860164006
Left: AD3-904, Right: I.R.-6-51 (Periods after I and R)

290861475348
Left: AD-1954, Right IR-1-4? (No periods behind the IR)

130849542854
Left: AD–1954, Right I.R-1-48 (Period only after the I)

150976684470
Left: AD4653, Right I.R.-7-5?

321031098946 – Pair
Left: AD5871, Right: Blank