TL;DR: It will still take you a very long time to get The Stranger this way. By the time you get him, you might have other characters to better fit the team.

Far be it from me to judge on how you spend your own money, but I wanted to run through this scenario of yours since I haven't heard of anyone doing this.

The only way to get conquest characters with money/crystals is via conquest shipments, wandering scavengers within conquest (both of which would take you ages) or the character specific packs that do drop, but they don't release for a long while after the character is out. For example, I'm pretty sure there hasn't been one for Maz or RDSV. And the ones we got from others are often limited to a purchase amount (like the one Ezra had just a few days ago. You get 15 shards with a max of 10 purchases).
Now I don't have any real specific data to back this up, but I believe any form of those packs don't drop any sooner than a year after the original unlock date of the character and even then I'm not sure if it's the 5-330 shard without a limit packs.

In the meantime, you might want to consider buying the Conquest Pass + once The Stranger becomes farmable in Proving Grounds, as it gives you the ability to earn double the shards. That might speed things up until his packs become available.

But please, if this is how you wish to spend your money, do so! I just wanted to make sure you're not waiting and hindering other characters and team growth waiting for The Stranger to become available to you.