An alternative if you dont want to deal with the potential hassles of traveling with a suppressor is simply to have your PH either buy one that has the correct thread pitch for your rifle for you ($150-$300 depending on what you want)
and then just "gift" it to the PH/Outfitter when you leave (pretty small expense in the grand scheme of things when you look at the total cost of a safari).. or, ask if your PH has a suppressor in camp that you can borrow/lease for a small fee, and then get a thread adaptor that allows his suppressor to connect to your rifle (generally about a $20 investment for a decent thread adaptor)..
Most of the camp guns for PG have suppressors on them at
@Bos en Dal SAFARIS .. and I know of at least 1 suppressor (.30 cal) that was purchased and then left behind by another AH member that could probably be used if he was asked nicely... I'd guess most other camps have a similar situation (suppressed camp guns and potentially additional suppressors laying around available for use while you are in camp)...