If I were to find items off of amazon I would start by picking the lowest price item as something that would be somewhat of a joke like this creeper hoodie or something that you would not normally wear or use but something to remember the good times spent to win it.
Another prize for around 50 would be some of the light up light strips which seem to be in high demand, I know a lot of people that have them. For the prize around 100 dollars I would get a decent mechanical keyboard, headset, or mouse. I really like Corsair and most of their products fit around 100.
For Around 150 I would get airpods. I know a lot of these items are rather basic things so they might not make for a good impression on a personality test but I think it’s very important to choose items that as many people as possible would enjoy and want to have.
The most important part of a give away: People LOVE free stuff. So its pretty hard to mess up a give away especially when you pick a great prize, which is why picking one that is related to the giver. When selecting a prize its important to chose something that relates to you or your group that is giving the thing away. Here is what I came up with: game/server perks that otherwise cost money. tons of servers these days have this type of thing, they offer perks and rewards in game for a real world cash price. Every player wants these but many are hesitant to get them, so I think giving some away would be a great opportunity to have the players get their hands on some and if your lucky those how do will tell other people about how good they are and you could get even more people to get them($5-$?).
Google play or iTunes gift cards. Gift cards are a staple for any good give away. They make a great one time reward and can be used for giving out prizes to people that didnt get the bigger substantial prize. Gift cards are great because anyone can use them, they are easy to get and give, and everyone enjoys getting one ($5-$25). Minecraft merch (or server merch if applicable) Since the people that are going to be taking part in this give away are all players on the server and subsequently Minecraft players there is a very good chance they would like to get free server or Minecraft merch.
There are tons of different merch optiosn which is what makes this a good idea and the player that wins could even have the option to pick what they want from a collection of pieces ($20-$50). Lastly: computer stuff everyone needs a computer to access Minecraft so giving away attachments, decorations, or equipment is a perfect idea. This also gives a ton of options to choose from which can range from stickers, headsets, monitors, speakers, or a plethora of other things ($60-$?).