NordVPN (https://nordvpn.com/?utm_expid=.J-Iv6ZU7Q0uR77_1Q1pVig.0&utm_referrer=) is having a sale but it looks like it's only going to last another 9 hours. $2.99/month on a 3-year subscription. They have a 30-day money-back guarantee and they appear to support Linux.
The pricing is in USD, so for the cheapest rate with a 3 yr plan you have to pay, up front $107 USD.
Yeah, should have mentioned that it's in USD.