@KorAgaz
If you're not going o buy Wampa shards with GET currency, then you really **must** get Wampa shards from the Galactic Bounties 1 event. It's the only other source in the game for Wampa. There are only 2 chances to get shards from the event each time it comes around, which means you can't get other toons from there, but trust me. All of the other characters are easier to achieve than Wampa. Wampa is on the "deadly" (final) tier of GB1, but beating that tier is a very achievable goal.
To beat the event you can use a g8-9 The Mandalorian (for his instant disintegrate) with a zBossk (to keep Mando alive until the final encounter) + other toons that stun (dengar, cad bane, Aurra) or ability block (Boba).
Or you can use g11 bounty hunter toons that stun & ability block. If Wampa gets off her special a single time, the fight is likely over.
In any case, GB1 offers you only 2 shard opportunities. I strongly recommend that you don't use them on other toons. If you focus on Wampa, from the first time you can defeat the deadly tier, you'll get 20 shards of her every 50 days or so (that's how often the event returns). So in another 350 days, you'll have 160 shards and can unlock her.
It's a very slow way to get the toon, but it avoids spending GET1 which is the second most valuable currency in the game, while still making progress towards Jedi Luke who is one of the most valuable toons in the game, especially comparing the return on investment, since he only costs about 1/2 the investment of GL toons but can win Challenge Tier-3 assault battles and LS Geo TB battles just as well as any GL. The only areas in which a GL is better right now are Squad Arena & the Rancor Challenge Tier.
In truth, you'll probably eventually spend GET1 on Wampa rather than waiting the full 2+ years to prepare your bounty hunters & then get her to 7* through GB1, but gearing up your bounty hunters sooner will get you Chewbacca and then speed up your eventual Wampa farm (and make it cost less GET) for every time you cycle through the event.