If you can get the truck cheap enough to where you won't be too upside down in it by the time you put a new motor in it....go for it! You will need a 4.7 with a 32 tooth tone ring. The 4.7's up to around mid year 2003 had 16 tooth tone rings....just an FYI if you get tempted into a used engine. The 4.7 should be fine with the towing/hauling chores you listed. I wouldn't hesitate to pull a small utility trailer with lawn mowers, or pull our jet ski trailer with 2 skis, or a reasonable size boat/trailer. Link below to where I bought our engine. I was VERY pleased with the whole transaction. Look on there and dig around. I tried Carolina Machine Engine first because they were close. They acted like they were bothered by me calling to ask questions, so I said F em! Jasper didn't impress me much, and the offerings from chain parts stores didn't either. Best of luck to you.

https://www.powertrainproducts.net/