Japan and APO shipping questions

Hey guys a few questions I have been feverishly trying to get my imported that is bringing my truck to Japan to get the transmission TSB done and the dealer is telling him its not applicable because of the build date, although haven't go confirmation that it is done. Im having a hard time finding people who will ship larger items to APO, although some like the OEM bedmat I found on Amazon. Couple questions below...

1. If it gets here and has stumble issues I don't think any Japanese Toyota dealer will reflash it so is OVtune my only option, or just living with the (possible) stumble condition until I return to the US?
2. Second is APO shipping I'm looking at getting some sidesteps or cheap sliders (I'm 95% sure I wont need sliders) anyone have recommendations for some that can be shipped to APO?
3. Back to APO shipping I'm planning on putting blizzaks on my stock rims here as it snows over a hundred inches a year here during winter, Id like to get a set of TRD SEMA Pro wheels over here but no one seems to want to ship them to APO, any recommendations?
3b. If I cant get the SEMA wheels here I was just thinking bout having the tires swapped out during winter/summer seasons, I know once or twice wouldn't be an issue does anyone know if this will shorten the life of the tires if I kept having them swapped on the same wheels?