Please Help Identify This 1cent Stamp

Hello again, this measures 19.25mm x 22.5mm has 11 perf on all 4 sides

my guess: SC # 498

This might be a #538 11x10, you have to check the perts. The cancel makes it difficult to tell from this scan. If it is perf 11 then 498 seems likely.

It measures 19.25 mm X 22.50 mm and is perf 11 on all four sides. I believe it is a rotary stamp please advise

Doesn't look like a rotary. A larger, clearer scan would help us to get a better look at it.

No need. The stamp is from a flat plate printing. Rotary press stamps of the period do not exist in such a bright shade. Also, the margins are too large to be a rotary press stamp. Try comparing the height and width of the stamp with some other low denomination stamp from the same series. The problem stated with attempting to measure the stamp. Comparing with another known stamp is faster and more accurate.

Clark