Verified answer

It's quite a strange word. Most Japanese won't understand it either.

In my opinion it could be an inside exclamation or some phrase used in his dialect, which is a typical thing to do.

It could also be ぎゃっ+ぶり.

ぎゃっ is a shout/shriek + ぶり, a suffix which means "after [some time/thing]"/"for the first time since ~".

So ぎゃっぶり could mean, "[I'm here] for the first time since my last shout!"

This is all guesswork. You better ask him directly.

It's a good excuse to start a new friendship. {^|^}

Wei ~Ya~tsu first time

...got it from google translate o.O