Speaker cables if your amp isn't between your speakers

Hi, I'm hoping for some advice on upgrading my speaker cables. My amp (and the rest of my equipment) sits to one side of my speakers. This means one  speaker is about four feet from the amp, and the other is 10-12 feet. I'm thinking of upgrading my speaker cables and it seems I either need to buy a set of cables 10-12 feet long or buy cables that can be ordered to length.  Buying a matching pair will obviously cost more and will be less tidy. Ordering specific lengths seems to decrease the choice significantly (at least in Australia where I live). I'm interested in what others have done in this situation. Spend the extra and deal with the mess, or go custom. My speakers are Wilson Audio Duette series 1 and my amp is a Plinius integrated. My current cables are the base model anticables   Thanks in advance.