とこ verb

[KabutoTX]

Ran across 買っとこ today. I assume this is a shortened たところ or maybe ているところ?

 

[Majestic]

Hard to say without the context, but probably a contraction of 買っておこう.

JLPT N4 Grammar: ておく (te oku) Meaning – JLPTsensei.com

Learn Japanese grammar: (te oku). Meaning: to do something in advance. This may also be used as: ておきます (te okimasu). ておいて (te oite).

jlptsensei.com

When used colloquially, it shortens to 買っとこ

 

[KabutoTX]

Yep. I was able to google that and find some examples. Thanks!
That was the whole tweet. So I guess a translation would be to preorder? (to buy in advance)

 

[Majestic]

It's sort of like someone voicing their intention. "I'd better buy that" or "I'd like to buy that at some point in the future"

 

[Toritoribe]

I guess a translation would be to preorder? (to buy in advance)

That's right. It's "to buy in advance (for a purpose)."
The volitional form, i.e., 買おう is used for the case Majestic-san mentioned.