You don’t need 4-figure cables for your gears to sound good. If your setup does not sound good with cheap and affordable Canare, Mogami, Belden, and Supra cables/cords then investing in 4-figure cables are not going to alleviate the situation. Just tell your dealer you don’t need any cables now and you are going to source them yourselves.
BUT, and this is speaking for my own experience, 4-figure cables do provide very noticeable improvements if your speakers and gears are reasonably high end and resolving. I used to use Furutech’s affordable finished cables that cost around 100-150$ each (they are cheap if you buy them direct from Japan) along with Belden and Supra cables. Moving up to cables that are around $800-$1000, the differences are not subtle. Soundstage, imaging, bass quality are two traits that really benefit from cables and cord upgrade. I have since upgraded all my cables/cords to 4-figure ones, BUT I did not actually spend 4-figures on any of them. I bought them all save for one either used or old stock. And I replaced the cables one at a time, carefully auditioning them to ensure the improvements and tonal changes were what I wanted.
Once you are used to the sound your new setup with cheap cables, you can ask the dealer to allow you home audition a premium cable to let you form your own judgement, or you can try a cable that has a return policy like Synergistic. If you don’t like what you hear, then don’t buy it, as simple as that.
A couple of options that are not rear ported came to mind immediately.
Triangle Comete Ez.
GoldenEar BRX.
A little bit more budget you can get the newer Mission 700 and Wharfedale Aura 1. Both of them are not rear ported as well.