Good sources:
European:
https://www.amazon.co.uk/Sicques-Tigers-Thieves-Eyewitness-1606-1809/dp/1403962014/ref=sr_1_2?crid=MNBKUMJ01FCX&keywords=siques+tigers+and+thieves&qid=1684585079&sprefix=siques+tigers+and+thieves%2Caps%2C87&sr=8-2
Not read this one, and can't find any reviews:
https://www.amazon.co.uk/Kings-Lahore-Empire-Through-French/dp/1911271091
Persian (free ebook):
https://www.vidhia.com/Historical%2C Political%2C Philosophical and Informational/Sikh_History_From_Persian_Sources_-_JS_Grewal_Irfan_Habib.pdf
Sikh (free downloads):
I think (for me), one of the best sources on puratan Sikhs in Gurmukhi is Rattan SIngh Bhangu's Panth Prakash, you can get english translations here:
https://www.scribd.com/doc/54832175/Vol-1-SRI-GUR-PANTH-PRAKASH-by-Rattan-Singh-Bhangoo-Trans-Kulwant-Singh
https://www.scribd.com/doc/149671030/Vol-2-SRI-GUR-PANTH-PRAKASH-by-Rattan-Singh-Bhangu-VOLUME-2-English-trans-by-Kulwant-Singh