I know Spicery gift sets have been mentioned before as a gift idea. They have a "buy one, get additional ones for half price" until 31/10/2018 on their Curry legends kits with cookbook and I have a referal code chris-32489 which might get you an extra 10% off.
DH had the Curry Legends kit with the hardback book for his birthday and we've really enjoyed using it.
www.thespicery.com/currylegend/the-books