Pure OCC silver at your stated price point will be hard to find and at .5 meters so will much in the way of flexibility.  At your price point and based on my personal experience I would look at the Ricable Supreme Mk II which is OCC Copper and Veritas Optimus 50 which is a blend of silver and copper.  Both great sounding cables at good prices.

DH Labs Hdmi 2.1 (tried / liked / kept) & Veritas Optimus 50 (going to try; some Ager likes it over DHL)

The third one worth trying is also silver plated (6%) 24awg Cardas copper recommended by iiwi.

Pangea Audio Premier SE MKII HDMI Cable 0.6 Meter

I was unaware of the Ricable Supreme Mk II, and I've been researching for awhile now.  I see that it features 24 awg conductors.  The Voodoo Silverstream does as well but they don't disclose materials.  I wish more cable companies would disclose material composition.  I realize it does not always correlate to sound, but still, would be interesting it know.

The shortest Voodoo Silverstream HDMI cable appears to be 0.9m, which is almost twice longer than what the OP is looking for. For reference and just for the sake of discussing material, I found thru. TCC's recommendation that Voodoo manufactures a true 75-ohm pure silver coaxial cable—possibly the most affordable option under $300 one could find in the market.
 

I can recommend the AVPlay HD-300 which I use between Gaia and Terminator Plus. It beat out the Tubulus Concentus V2 in direct comparison. Tubulus Concentus V2 was a bit sharp and bright in my system even after 200 hours. The AVPlay HD-300 is clear with body, texture and 3 dimensional soundstage. 

Wireworld makes 0.6 meter high end HDMI cables, the Platinum Starlight top of the line one is $800 MSRP, the next step down model is silver clad pure copper for $250 MSRP for 0.6 meter...