Any way to limit a store to a certain area/postcode?

Hello,

Basically I have a few different stores which are across the UK. My current issue is that say I have two stores, one in Manchester and one in Liverpool and the client lives in Manchester but on the border and they’re nearer to Liverpool but not actually in Liverpool. The issue is that the client would contact the Liverpool store (due to it being closer to him) instead of the Manchester store when ideally we want them to contact the Manchester store as Liverpool doesn’t serve the Manchester area.

Simply, I just want to be able to limit a certain area/postcode to one specific store, so the others that may be nearer but not necessarily serve their area.