Interconnects under 300

I'm currently using a marrow sa 2 from my pre amp(marantz 7005) to amp (mccormack dna1 gold rev)
is there any interconnects that you guys have used that would be night and day difference under 300?
Btw I use kimber 8tc and Nht 2.9 any suggestions

Don’t know about night and day difference but I’ve replaced some Morrow MA4s pre 2018 design (with KLE Pure Harmony RCA plugs) with, firstly, Atlas Equator OCC Integras and, more recently, Mark Grant Cables HDX1.

The Atlas pair were less than half the price of the MA4s. The HDX1s were less than a fifth of the price of the MA4s. As I posted elsewhere on the web, I found the MA4s had a tendency to sound bright and, with some recordings, brittle. With both the Equators and the HDX1s, music sounded smoother at higher frequencies and, to me, had the edge over the MA4s on sound stage width. I preferred the HDX1s because the bottom end was slightly firmer than the Atlas but, for me, both comfortably displaced the MA4s.

On these very forums, Black Cat Coppertone interconnects have been discussed, mainly positively. However, I don’t have personal experience.

I also tried Mogamis (2497 cable) but, unlike many many other posters on these (and other) forums, I was truly underwhelmed. YMMV :) .

Happy hunting...
Check out the Acoustic BBQ cables. I've tried a ton of different cables ranging up to $2-3K over the years, and Bill's cables are competitive with anything I've had. They are also affordable. Highly recommended. I especially like his Schroeder-style interconnects. Very natural and musical.

Good luck.
Take a look at KLE Innovations

Even though I have not tried this model, I have tried most of their lineup and they make some extremely good cables that perform exceptionally  well.

The price is Australian dollars, so with the conversion they are within your budget

Regards - Steve
I’ve had great luck with Transparent MusicLink cables. They destroyed my Audioquest Big Sur cables in terms of sound and definition.
Kimber Kable Silver Streak, here used for $300 is a very good cable.
I was looking at the specs on these and I was comparing them to other to the numbers work 
is the lower number the better?