I recently re-barreled a custom sporter with a new Criterion barrel. I was in the same boat as the OP in that I wanted to retain the 24" barrel length. I simply bought a 30" Criterion and cut it to 24". The lack of a front sight mortise didn't bother me as I sweated on a ramp front sight. I couldn't be happier.

The advised "short chamber" didn't materialize either. The chamber was perfect from the factory. Minimal headspace with zero stretch marks on fired brass with arsenal-level loads. Accuracy beats any obtained with a plethora of Krags I owned in my life.

I wish Criterion had been around years ago when I pulled my hair out getting a couple of ornery Krags to shoot!

Not recommended for placement on guns for which originality is a concern, but is a panacea for sporterized guns whose barrels are getting "tired".