Just read the
RELEVANT THREAD and find someone as local as possible, then try contacting him using the Personal Message or the email as to arrange for it.
Pandora Battery Set (Battery + Stick) will be enough to install CFW in your Slim PSP.
Consideing it´s a Slim PSP your PSP would have to go straight to 3.71 M33-2 Firmware once you´ve used Pandora´s Battery (with el "Despertar del Cementerio" or Universal Unbricker from
Dark_Alex).
Once in 3.71 M33-2, it´s recommended that you install the Patch No 3 (Available from Dar_Alex´s Homepage).
Beware that the 1.50 Kernel Patch is ONLY for FAT PSPs, so Slim PSPs cannot run old homebrews based on 1.50 kernel (Mostly all homebrew being released nowadays is based on 3.xx kernel so most of the new stuff you´ll be able to use)