no-one coming to visit you who can bring it to you or visit home planned so you could bring it back as checked-in?
trouble with shipping liek that (P-force etc) is you get into customs declarations, which can turn into a nightmare depending on the system in the country your importing into. I've not lived in Ethiopia but I can tell you that china is a bl**dy PITA, I'd sooner fly to london and bring the stuff back in check-in.
how about asking the guys you're working with, perhaps VSO can help out?
good on you for doing VSO btw, I hope you're enjoying it, I know there's sod all cash in the system and you're effectively volunteering so props to you