My references: Scotts 2004; stampsmarter; Swedishtiger; the dubinweb site about stationery; and this site.
I feel like I've been there, done that with this stamp but I am still perplexed. Here's what I know: It's design A33 (design of the 1861 issue); on cover with a U58 (or 59) which was issued in 1864-65; cover cancelled Nov. 13 (no year) handwriting on the back of cover indicates 1869 as does letter inside (dated Nov 11 1869). And it's registered mail.
The stamp definitely has a grill I'm pretty sure it's the F grill BUT I'd like to throw it out to you just to make sure it's not an "E" grill To me it measures 11x9mm. Points are pointing down.
Thanks in advance!
scan is 1200dpi. I tried changing contrast, etc. and it didn't seem to help me at all so this is just the plain scan.