It might work but possibly not very well. For one thing, your 250K pot is probably audio taper, and was intended for audio-stage control. This Philco volume control works by attenuating the incoming RF signal, and should be linear taper if using a carbon-track pot. It probably originally was a wirewound pot.
You can't hurt anything by trying a different pot in the circuit. But, you may find that it behaves very oddly in terms of how it controls the set's volume.