You don't directly convert dosage across species like that. The dosage they tested on monkeys was 250mg/kg, and the human equivalent would be less than that.
I see that Amazon sells 1 gram capsules of taurine (several vendors). So, yeah, not too difficult to consume. One brand I saw is about $0.08/gram, so it wouldn't be overly financially burdensome, either.
> Serious adverse effects have not been reported with taurine supplementation.[24] The highest dose used in a human trial was 10 grams per day for 6 months, and the longest human trial was 12 months and used a dose of 0.5–1.5 grams per day. Based on the available evidence, it’s suggested that 3 grams per day can be consumed indefinitely without risk of side effects.[24]
IOW they gave the mice a dose of taurine that, proportionally, i'd be unwilling to take.