Someone that is more involved with recruiting and ops can probably tell you more, but for expats minimum requirements for Immigration is 1000hrs TT. Most companies require something along the lines of that figure for PIC, 1500hrs for Caravan.
One company recently introduced a cadet scheme for Tanzanians with ( if I recall that correctly now) something like 250-300hrs TT and a valid CPL/IR. That seems to work out well for everyone and is a win-win for everyone.
The rest is down to insurance requirements like anywhere else.