RG-213 is roughly the equivalent of old mil-spec RG-8. Great if you are running an 1000-watts RF output with a HF (shortwave) amateur radio station. Probably way more than anyone needs for transporting audio, but otherwise, yeah you could use it.
I dabble in RF more than audio. Audio frequencies are *very low* compared to most common RF purposes. For example a 20000Hz analog signal is 20KHz. Coaxial loss at 20KHz tends to be minuscule even at moderate distances with all but the most garbage of feedline.
You can use a RF coax loss calculator for a general idea of loss if truly interested. For example, if again using 20000Hz audio, enter the frequency as .02MHz. Load is 1:1 due to both connected devices being approximately 50 ohms. Select the coax type, then look at the matched loss.
https://www.qsl.net/co8tw/Coax_Calculator.htm
Loss at 20KHz for a 90m run of Belden RG-58 is 0.148dB. Probably not worth concerning yourself assuming you are using coax of similar quality, be it Belden, Davis, etc. You likely will fair better with RF or CATV suppliers instead of audio suppliers for coax pricing. Also, if you are buying a cable made to your length, ask for Amphenol or similar quality connectors to be installed.
As noted by Bojcha, shielding can be a concern if in an environment with lots of EMI/RFI. Common RG-58 is single-shielded design. If needing to deal with EMI/RFI mitigation, a dual- or even quad-shielded coax can be used.
With EMI/RFI noted, commonly available RG-6 quad-shield coax could be another good option. It is 75-ohm feedline, but the impedance mismatch losses are not enough to matter for audio purposes IMO. You can buy it at common lengths with F connectors already installed if desired, and decent F connector to RCA connector adapters are readily available for low cost.
Run a vector network analysis on cheap bulk RCA-style audio cable anyway, and you likely will find the impedance to be all of over the place, from way under 50-ohms to even over 100-ohms. o.0