honestly i would just buy a private header from someone reputable, afaik powersaves only works on a handful of games for sky3DS (only card2 games like pokemon), imo its a waste of money for just getting a private header, for like £5 someone would be able to buy a crappy game rip the header for you and send it to you an dispose of the game, i have done it for people before although i just kept the game (PS im not using it, but as a collector i just kept it on the shelf so i know the header will never end up in someone elses hands)
or you could even just buy another 3DS on 9.2 or lower and sell your current one after doing a system transfer to the new one, even if you spend a bit more on the new console than you get back on the old one you will probably still end up better off, lets just say you buy one for $100, sell yours for $80 your still about $60-80 better off (for the sky3DS and powersaves) and get all the benefits of save editing, eshop games etc that arent possible with sky3DS directly