sutcliff_space | Anyone got an old edition of Outcast?

I re-read Outcast recently and noticed some eccentric spellings I hadn't ever noticed before. It turned out that the 2012 Oxford University Press (UK) e-book I was reading and the 1995 Farrar Strauss & Giroux (US) paperback I had previously read differ slightly on these words. I also looked at a 1999 Oxford paperback edition, which predictably agreed with the Oxford e-book. I'm curious to know how far back these textual variations between UK and US editions date. So I'm hoping that some bored readers might a) have older editions of Outcast and b) be willing to check a few words in the text!

1. End of chapter 6: the scene between Beric and Glaucus mentions two Roman coins. Oxford 2012 and 1999 call them a gold "aurus" and a "sestercia". Farrar Strauss Giroux 1995 has "aurum" and "sesterce". (I believe it should be "aureus" and sesterce or sestertius.)

2. Start of chapter 7: the cook is identified as a "Campagnion" in the OUP and "Campanian" in the FSG. (Campanian is the usual spelling.)

3. Start of chapter 9: Beric grabs a rake used for the "hypercaust" in the OUP or the "hypocaust" in the FSG. (Hypocaust is correct.)

4. End of chapter 10: Beric is held in the "Mamatine" prison in the OUP or the "Mamertine" in the FSG. (Mamertine is the usual spelling.)

5. Start of chapter 11: The scene opens in Colonia "Agripensis" in the OUP or Colonia "Agrippina" in the FSG. (Wikipedia says Cologne was called Colonia Claudia Ara Agrippinensium at the time of the story, in the 2nd century, and Colonia Agrippina in the 4th.)

There are a few oddities that appear in both editions, like "Silurium" for Silurum in chapter 1, "Lybian" for Libyan (or Lydian) and "debit" for "debt" in chapter 11. I would also like to know if "the Kailhan" descended from the stables of King "Soliman" in chapter 15 is meant to be Arabic "al-khayl" or "al-khail", meaning horses/the horse according to my Google results.

To me it looks as if the FSG text corrected (in some cases hypercorrected) spelling errors in the OUP text. Misspellings of loanwords and proper names are fairly plentiful in Sutcliff novels. (Spelling in general was not Rosemary Sutcliff's strong suit, according to a correspondent of hers.) But without looking at the oldest editions – OUP in the UK, H.Z. Walck in the US – it's hard to tell. It could be that the original OUP text was fine and these are misprints in later editions.

So, if anyone feels like helping with this, please tell me what edition you're looking at and which spelling it contains!

(I'm not sure if anyone here is interested in like... Tolkien fandom levels of nerdery when it comes to Sutcliff. So if you read this far, thanks for indulging me.)