That's a good one but you can Go for this on cheaper side - https://www.amazon.co.uk/Breville-SuperSteam-Ceramic-Soleplate-VIN412/dp/B0942ZYRYG/ref=mp_s_a_1_18?crid=3DBTMOT7MHB1P&keywords=iron&qid=1668777604&sprefix=iron%2Caps%2C1080&sr=8-18
These were ideal for me, as previously stated, be careful as if they are to small the lockers can still be opened!
You can buy a practice book off amazon for about £9.45, it's really good I managed to pass using this book. And It has all the different topics you would get in the actual test. Here is the link: https://www.amazon.co.uk/RAF-Airman-Tests-questions-Testing/dp/1909229911/ref=mp_s_a_1_1?dchild=1&keywords=raf+airman+test+book+2021&qid=1626299003&sprefix=raf+air&sr=8-1
RAF Airman Tests: Sample test questions for the RAF Airman Test: 1 (Testing Series) https://www.amazon.co.uk/dp/1909229911/ref=cm_sw_r_cp_api_fabc_VDX1V0YHAK0EW4AER3S1
If you’re unfamiliar with stuff like mechanical and electrical or just want a refresher on maths etc grid book will help you. It helped me