https://www.facebook.com/photo?fbid=10169712178659852&set=pcb.1384116267240477
Smith-Corona rebrand with a Standard Elite No 66<br />

https://www.facebook.com/photo?fbid=10169712178659852&set=pcb.1384116267240477
Smith-Corona rebrand with a Standard Elite No 66<br />

https://www.facebook.com/photo?fbid=10169712178549852&set=pcb.1384116267240477
Smith-Corona Sterling 12 typeface with foundry mark

Princess 300 with RaRo Elite Imperial typeface
The "AR" foundry mark is a shorthand for Albert Rodrian, one half of RaRo. If you ever see an R inside an octagon that's the mark for the other half, Alfred Ransmayer.
The "84" on the foundry mark is typical of RaRo's 12 pitch Elite Imperial which can be found with a sample at: https://typecast.munk.org/2023/02/04/1961-adler-typewriter-type-font-styles/
You can also compare other known Princess typefaces at the database: https://typewriterdatabase.com/twdb.0.typefaces?mfr_search=70&model_search=100#
If you put a ruler up to your type, you should find that there are 12 characters per inch.
You can also cross reference the following: - the Hass catalog, page 3, row 1:<br /> https://archive.org/details/typewriter-foundry-marks-haas/page/n1/mode/2up<br /> - RaRo Catalogue Page B3-4 "Elite-Schatten Ro 84":<br /> https://www.sommeregger.name/typewriters/files/RaRo/rarotype_katalog_1980_OCR_20160523.pdf
Reply to u/CaptainCulinary at https://old.reddit.com/r/typewriters/comments/1wjb0gk/princess_300_with_typeface/
the mark says AR for Albert Rodrian, one half of RaRo. If you ever see an R inside an octagon thats the mark for the other half, Alfred Ransmayer.
via Koponewt (aka Otto Koponen) https://www.reddit.com/r/typewriters/comments/1kg83kz/olympia_typeface/
Not exactly, no. Ro85 and Ro87 (Pica and Elite Cubic) are very close to OP's type sample but the W's have sloped sides and the numerals are different. It's not a copy of Sentorial either, the most apparent differences are the Capital Q and K. I could not find Ro83 in any of my catalogs either, it's a bit weird. I've seen RaRo slugs on Olympias before, it's possible this was something they only did for them. Ro87 Elite-Cubic: https://i.imgur.com/3seKddd.jpeg Olympia Senatorial: https://i.imgur.com/yuTlzQh.jpeg