Each time you vote for the server through a vote server (website) you get a few rewards (see the rewards page), including special unique vote-tokens. Each site has their own specific token. And each token type is linked to a special unique op item.
The short answer is no, but, obtaining them is meant to be done only through voting and exchanging vote tokens with a server owner. Technically if someone has an op item, it's sort of just theirs. However, sometimes people wish to gift special things to their friends, or sell it for /money on the global /market. Exchanging or gifting these special tokens and/or op items is allowed.
At the beginning, there are zero vote tokens and zero tiers. The moment you vote once, you unlock Tier 1. You are at this point eligable to exchange 64 vote-tokens of the same type (so all diamond vote tokens or all iron vote tokens..) for their linked items.
Since there are six websites that can be used daily to vote through, there are six different types of vote tokens. And that means there are six different types of OP items for the first Tier.
If you have collected all six OP items from Tier 1, you have unlocked Tier 2. This is also the only way to get access to the items from Tier 2. Tier 1 has 1 layer of 6 items, Tier 2 has 2 layers and 12 items, and tier 3 has 3 layers with 18 items.
Once you've unlocked Tier 2, and you've collected all tier 2 layer 1 and layer 2 items, you've unlocked Tier 3. There is no Tier 4.
Each layer is "6 things" or "6 items",
Tier 1: There are 6 items, and there's only 1 layer.
Tier 2: There are 12 "things", not all are items! And Tier two has 2 layers (2x6)
Tier 3: There are 18 "things", not all are items! And Tier three has 3 layers (3x6)
Yes, it's a Survival Server, losing an OP item reaaaaallly sucks, but it's part of game-play. Always report it to us, if you catch a server owner in a good mood, you might just get it back (very rarely!)
Note please that you're free to use any vote tokens as you see fit. Throw them in lava, sell on the global /market for $45,000 or use /trade to gift it or exchange it with another player. You can also go to /warp vote, and sell them back to the server. Per 16 tokens, you can get $64,000. The most value lies in exchanging it for the OP item(s) it's linked to.
Contact a server-owner, because only a server owner can exchange 64 vote tokens of the same type, for the unlocked Tier (item/thing) it's linked to. If there's a choice to be made between various items, you will be shown the things/items, and you have an option to ask questions about it.
Not all Tier items are actually items. Sometimes it could be a one time access to a command, or unlimited access to exclusive features. It could be a tool or armor with impossible enchants on it, or maybe access to get your own world! In Tier 2 for example, there's a Conduit Box which holds even more items to help you build conduits.
Check on the left on the Tier 1 / Tier 2 / Tier 3 pages, to learn what's available for each layer, per Tier.
You can contact us in-game, on discord, or on the forums