Really cool Disco, they're still one of my favorites. Bummer about the engine troubles, but at least the vendor stepped up and covered a new engine for you. Much like the 4.7 in my WJ I know heat is the enemy of those 4.6s... have you already done cooling mods (apologies if you already covered that, I haven't gone through all the pages of your thread yet)?
As for the winch, I just bought this:
Smittybilt X2O 10K Waterproof Synthetic Rope 10000lb Wireless Winch Gen2 with Fairlead - 98510 but it was on sale another 10% off (so I paid less than $500 with tax and shipping). I have friends that have run them with great success (no issues). For the price it had all the features I wanted (synthetic rope, wireless control, etc.) so I tried not to get too hung-up on name brand stuff. I got a hidden winch mount for behind my bumper until I can do a "real" bumper down the road. It's the Gen2, and the Gen3 is out... but I couldn't justify $200 more for basically just the slicker looks of the Gen 3 since it'll be behind my bumper. In fact, I like the plain fairlead of the Gen2 better, since that's all that will be exposed. My WJ should be about 4300lbs itself stock, so probably 4500lbs as it will sit with the lift/wheels & tires/winch etc. Add me and some gear and it's over 5k I'm sure. The "rule of thumb" for winch sizing is 1.5x the weight of the loaded vehicle, so I "should" have at least a 7,500lbs winch. At $10k this one is about double my loaded vehicle weight, so I couldn't justify the extra $ to go up to a 12k. Even if you go by GVWR for my WJ which is 5,500lbs then I should be at 8,250lbs for the winch, so 10k should be great.
-TJ