Good point.
Figure 15-20 very rich families and their servants, at the very least multimillionaires just to contemplate a project like that, possibly billionaires. They could collectively throw a couple billion into a project like this. About a billion credits buys a couple of jump-3 1000-dT cargo/passenger carriers, with 200 dT of cargo room converted to fuel tankage for a jump-3/jump-2 sequence and around 200 dT for whatever balance of passengers and cargo you decide on. (The Oberlindes CT out of Traveller Adventure works well in this capacity and is relatively inexpensive at ~MCr400.) That's the biggest cost.
(A jump-4 freighter with 100 dT of cargo converted to fuel tankage costs a chunk more and loses a bit of cargo/passenger room but makes for shorter trips, allowing the Far Place to Faplion/Sent'ere leg to be taken in 1 week.)
I still think you need combat armor, even if you equip them otherwise to TL 8. Your biggest problem is going to be deploying the force. Even if it was 50 years ago, you've got to have some rationale for how you got the force in position. You're billionaires with 1000-ton ships at your reach, not navies with 100,000-ton troop transports; you can afford better once you master the planet, but initial deployment's only going to be about a company or two (or perhaps that amount every 2 weeks). The better armed and armored your men are, the more potent they are, and the more you can accomplish with a small force. If you're importing troops from afar and stranding them on a TL 5 world, you're not limited to the master world's TL 8. Combat armor: no maintenance, no issue with keeping it fueled or loaded or repaired - it's just body armor, and there's precious little a TL 5 society can do to defeat it. A couple hundred men in combat armor could have strode through Verdun like hell's own demons.
Anywhere you want, I'd think. The kind of people who'd conquer a world for their own profit and amusement are likely to be TL 8 because it amuses them to have people serve them instead of machines. No fusion tech, but with their wealth they could set their colony up with a good-size solar farm for minimal maintenance and manpower needs. Very likely they're running plantations to meet their food needs - and for the joy of looking out the window and seeing people laboring in the fields instead of automatons. Farmhands sweating in the sun, using tractors burning home-grown biodiesel and maintained by a few mechanics using little more than the power tools you'd see in a modern auto shop. Enough parts and spares to keep folk working until a replacement can be shipped in. Some of those farm hands may well be Rill political prisoners wearing shock collars and ankle monitors.
It's less a matter of where they're getting goods than what they're choosing for goods. And because the bulk of the colony would be to TL 8 standards, the few high tech luxuries the elites reserved for themselves wouldn't be counted against the norm.
Candidate worlds for shopping or recruiting include:
Naagasa, a TL-9 world with a pop in the hundreds of millions, though of high law level, and
Voegrr, a TL-12 world with a pop in the hundreds of millions, and of very low law level (1).
Both are 5 (or 4) weeks from A'Tul, by going through Far Place and then Sent'ere. You shouldn't encounter too much trouble buying TL 8 goods at a TL 9 world, and you ought to be able to recruit without facing awkward questions at the TL 12/Law 1 world.
TDG?
