My "high torque" starter came from TRF, which was cheapest for me (check out their "Customer Investment Program).
I have heard that some of them suffer premature failure, because the wires inside the solenoid are not properly secured and vibrate under racing conditions. But mine has done the equivalent of about 5 years of daily street driving, with no problems at all.
But be sure you get the starter that matches your flywheel. It's not uncommon at all to find the wrong flywheel installed (for example, TS13571L should have the early version, but has an alloy TR4A flywheel installed by the DCO), so it's best to actually look at the flywheel. With the starter out, look through the hole for the bolts that hold the ring gear on. Bolt-on ring gear means you need the later type starter (10 tooth pinion, instead of the earlier 9 tooth).
As far as "rebuilt" Lucas starters on eBay, I would consider them <span style="font-weight: bold">at best</span> a core to be rebuilt. The last one I bought literally had blasting media inside the rear bearing cover!